PSSA Science Practice 2014-2015

Student Name _____________________________________________

Teacher Name _____________________________________________

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The  diagram  below  shows  four  Moon  phases  observed  during  July.  

 

   

On  which  date  would  the  next  New  Moon  occur?  

(1)  August  5    (2)  August  10    (3)  August  19  (4)  August  29  

2

The  surface  of  Earth  is  covered  by  a  relatively  thin  layer  of  water  called  the  

(1)  crust    (2)  mantle    (3)  hydrosphere  (4)  atmosphere  

3

In  which  type  of  rock  are  fossils  generally  found?  

(1) igneous    

(2) metamorphic    

(3) sedimentary  

(4) volcanic  

 

 

 

 

 

 

 

 

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4

Which  title  best  describes  the  processes  shown  in  the  diagram  below?  

   

(1)  The  Rock  Cycle  (2)  The  Water  Cycle  (3)  Plate  Tectonics  (4)  Chemical  Changes  

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The  diagram  below  shows  a  penny  scratching  the  surface  of  the  mineral  calcite.  

 

   

Which  physical  property  of  the  calcite  is  being  tested?  

(1)  streak    (2)  hardness    (3)  melting  point  (4)  reaction  to  acid  

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6

The  diagram  below  shows  milk  being  poured  into  a  measuring  cup.  

   

Which  property  of  the  milk  can  be  directly  measured  using  the  cup?  

(1)  mass    (2)  density    (3)  solubility  (4)  volume  

7

Which  energy  resource  is  renewable?  

(1)  fuel  oil    (2)  natural  gas    (3)  wind  (4)  coal  

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The  drawing  below  shows  the  original  size  and  shape  of  a  rock  sample  before  it  is  thrown  into  a  rapidly  moving  stream.  

 

Which  drawing  best  shows  the  actual  size  and  shape  the  rock  will  have  after  being  carried  several  hundred  miles  downstream  and  deposited?  

 

Answer is 3

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9

The  diagram  below  shows  stages  in  the  development  of  a  certain  landscape.  

 

   

When  did  erosion  become  the  most  dominant  process  in  the  development  of  the  landscape  shown  in  stage  4?  

(1)  at  stage  1    (2)  at  stage  2    (3)  between  stages  2  and  3  (4)  between  stages  3  and  4  

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The  graph  below  shows  tide  levels  for  two  days  at  an  ocean  location.  

 

   

Approximately  how  many  hours  are  between  the  high  tide  on  Tuesday  and  the  first  high  tide  on  Wednesday?  

(1)  6  hours    (2)  9  hours    (3)  12  hours  (4)  18  hours  

 

 

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Base  your  answers  to  the  following  questions  on  the  diagram  below,  which  shows  two  insulated  Styrofoam  cups  of  water  connected  by  an  aluminum  bar.  The  thermometers  show  the  temperature  of  the  water  in  cup  A  and  cup  B  at  the  beginning  of  a  heat-­‐flow  experiment.  

 

 

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Over  the  next  15  minutes,  which  changes  would  most  likely  occur?  

(1)  The  temperature  in  cup  A  will  decrease  and  the  temperature  in  cup  B  will  increase.  (2)  The  temperature  in  cup  A  will  decrease  and  the  temperature  in  cup  B  will  decrease.  (3)  The  temperature  in  cup  A  will  increase  and  the  temperature  in  cup  B  will  increase.  (4)  The  temperature  in  cup  A  will  increase  and  the  temperature  in  cup  B  will  decrease.  

 

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Which  process  is  most  responsible  for  the  temperature  changes  that  will  take  place?  

(1)  radiation  of  heat  from  the  water  in  the  cups  to  the  thermometers  (2)  conduction  of  heat  through  the  aluminum  bar  (3)  radiation  of  heat  from  the  water  in  the  cups  into  the  air  (4)  conduction  of  heat  through  the  air  to  the  water  in  the  cups  

 

 

 

 

           

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The  cross  section  below  shows  fossils  and  the  rock  layers  in  which  they  are  found.  Crustal  movement  has  not  displaced  the  rock  layers.  

 

Which  fossil  is  considered  the  oldest  in  the  cross  section  shown?  

(1)  armored  fish    (2)  dinosaurs    (3)  early  horses  (4)  trilobites  

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Evidence  that  living  things  have  evolved  over  hundreds  of  millions  of  years  can  be  found  in  

(1)  particles  in  the  air  (2)  rocks  containing  fossils  (3)  tree  rings  from  recently  logged  trees  (4)  chemicals  in  human  hair  

15

Extinction  of  a  species  is  most  likely  to  occur  as  a  result  of  

(1)  evolution  (2)  migration  (3)  selective  breeding  (4)  environmental  changes  

 

 

 

 

 

 

 

 

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Base  your  answers  to  the  following  questions  on  the  diagram  below  which  shows  a  model  of  human  inheritance.  

 

 

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The  parent  whose  genes  are  aa  

(1)  must  be  dominant  (2)  has  a  straight  hairline  (3)  has  a  peaked  hairline  (4)  may  have  AA  offspring  

 

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The  diagram  shown  is  called  a  

(1)  Punnett  square  (2)  pedigree  chart  (3)  dichotomous  key  (4)  flowchart  

   

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Some  kinds  of  fish  live  most  of  their  lives  in  salt  water  but  lay  their  eggs  in  freshwater.  Their  ability  to  survive  in  different  environments  is  an  example  of  

(1)  adaptation  (2)  developmental  stages  (3)  a  habit  (4)  selective  breeding  

 

 

 

 

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Which  example  would  result  in  new  cells  that  are  most  different  from  the  parent  cells?  

(1)  yeast  cells  splitting  into  new  cells  (2)  bacteria  cells  dividing  into  new  cells  (3)  skin  cells  dividing  to  produce  more  skin  cells  (4)  sperm  and  egg  cells  uniting  to  produce  fertilized  egg  cells  

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The  table  below  shows  the  symptoms  of  some  diseases  that  are  caused  by  bacteria.  

 

Which  two  diseases  listed  in  the  table  affect  the  digestive  system?  

(1)  botulism  and  typhoid  fever    (2)  botulism  and  pneumonia    (3)  tetanus  and  pneumonia  (4)  tetanus  and  typhoid  fever  

 

 

 

 

 

 

 

 

 

 

 

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Base  your  answers  to  the  following  questions  on  the  diagram  below,  which  shows  a  partial  food  web.  

 

 

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How  many  organisms  in  this  food  web  feed  on  the  mice?  

(1)  5    (2)  2    (3)  3  (4)  4  

 

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Which  group  of  organisms  is  missing  from  this  food  web?  

(1)  carnivores    (2)  herbivores  (3)  omnivores  (4)  decomposers  

   

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Populations  living  in  one  place  form  a  

(1)  community    (2)  system    (3)  habitat  (4)  species  

 

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Which  situation  is  the  best  example  of  ecological  succession?  

(1)  An  organism  survives  a  difficult  winter.  (2)  The  populations  in  an  area  remain  the  same.  (3)  One  species  replaces  another  species  in  an  ecosystem.  (4)  Each  of  several  species  uses  the  same  amount  of  resources.  

25 The diagram below shows a food web.

Which three organisms in the food web are competing for the same food resource? (1) carrot, rabbit, and fox (2) grain, bird, and owl (3) fox, owl, and rabbit (4) bird, mouse, and grasshopper

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Base your answers to the following questions on the table below, which compares human populations and carbon dioxide (CO2) levels in the atmosphere over time.

Human Population and Carbon Dioxide Levels

Year Human

Population (billions)

Carbon Dioxide (CO2) Levels in the Atmosphere

(parts per million)

1960 2.50 317

1970 2.75 325

1980 3.00 337

1990 5.00 342

26 How have the size of the human population and the amount of carbon dioxide (CO2) in the atmosphere changed from 1960 to 1990? (1) The human population has increased while the amount of CO2 has decreased. (2) The human population has decreased while the amount of CO2 has increased. (3) Both the human population and the amount of CO2 have increased. (4) Both the human population and the amount of CO2 have decreased.

27 Which human activity might explain the change in carbon dioxide levels shown in the graph? (1) storing nuclear waste (2) collecting solar energy (3) using wind energy (4) burning fossil fuels

28 The effects of natural selection are generally seen most quickly in which organisms? (1) bacteria (2) corn plants (3) humans (4) cats

29 Which substance provides humans with their main source of energy? (1) food (2) carbon dioxide (3) water (4) chlorophyll

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30 Weathering and erosion of Earth’s crust are primarily caused by (1) gravity (2) volcanic activity (3) evaporation (4) sedimentation

31 Which statement is true of all rocks? (1) Rocks contain organic material. (2) Rocks contain fossils. (3) Rocks are composed of minerals. (4) Rocks are formed in layers.

32 All matter is made up of particles called (1) cells (2) molecules (3) atoms (4) compounds

33 Note that this question has only three choices. As altitude increases, air pressure (1) decreases (2) increases (3) remains the same

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34 The graph below shows the water levels that result from tidal action over a 24-hour period.

What was the approximate height of the water on the tide marker at 6 p.m.? (1) 4.3 ft (2) 5.4 ft (3) 8.5 ft (4) 11.2 ft

35 If shell fragments are found in a rock sample, it is most likely that the rock formed (1) on a mountain slope (2) on a glacier (3) from magma (4) in shallow water

36 Which weather event usually includes heavy precipitation, strong winds, and surface air temperatures below 0ºC? (1) blizzard (2) hurricane (3) thunderstorm (4) tornado

37 Which term refers to the atmospheric conditions that prevail from season to season and year to year at a certain location? (1) weather (2) climate (3) equilibrium (4) ecosystem

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38 The diagram below shows three stages in the formation of a beach.

Which process is mostly responsible for the breaking down of the rock cliff into sand-sized sediment? (1) weathering (2) faulting (3) folding (4) precipitation

39 The diagram below shows a boy observing a fish located at position B below the surface of the water. The boy sees the fish at position A.

The apparent position of the fish is different from the actual position of the fish. What has happened to the light passing through the water to cause this difference? (1) reflection (2) absorption (3) compression (4) refraction

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40 The diagram below shows two dogs pulling on a rope with constant but unequal forces.

In which compass direction will both dogs most likely move? (1) east (2) west (3) north (4) south Base your answers to the following questions on the map below and on your knowledge of science. The map shows the origin of a maritime tropical air mass. The arrow shows the general track of this air mass. New York State is labeled NY.

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41 Which temperature and moisture conditions are associated with this air mass? **See Diagram from previous page** (1) cold and dry (2) warm and humid (3) cold and humid (4) warm and dry

42 Which factor has the greatest influence on the direction of the air-mass track? (1) upper air currents (2) ocean currents (3) sea breezes (4) mountain barriers

43 Which graph correctly shows the effect of heat energy on the motion of molecules of matter?

Answer is 3

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44 The diagram below shows the relative wavelengths for several types of electromagnetic energy.

Which type of electromagnetic energy has a shorter wavelength than ultraviolet waves? (1) visible light (2) microwaves (3) x rays (4) infrared light

45 Which energy source is considered a nonrenewable resource? (1) solar (2) wind (3) moving water (4) fossil fuel

46 A television set changes electrical energy to sound and light energy. In this process, some energy is (1) created (2) destroyed (3) changed to matter (4) changed to heat

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47 The cross section below shows sedimentary rock layers containing fossils.

Assuming that these rock layers have not been overturned, which fossil is in the layer that was formed most recently?

Answer is 2

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Base your answers to the following questions on the diagram below and on your knowledge of science. The diagram represents a pond community containing a variety of plants and animals.

48 Why are the fish able to survive in the pond? (1) The fish use carbon dioxide produced by the plants. (2) The fish use oxygen produced by the plants. (3) The plants use oxygen produced by the fish. (4) The plants use chlorophyll produced by the fish.

49 The main source of energy for this pond community is the (1) plants (2) Sun (3) pond water (4) animals

50 A new variety of tomato is better tasting and can be stored longer than other tomato varieties. This new tomato is produced by placing additional gene segments into the cells of the tomato plant. This process is known as (1) genetic engineering (2) selective breeding (3) natural selection (4) sexual reproduction

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Base your answers to the following question on the cross section below and on your knowledge of science. The cross section compares the densities of different Earth layers.

51 Which Earth layer is most dense? (1) plastic mantle (2) stiffer mantle (3) outer core (4) inner core

52 Convection currents, which may be the driving force for the movement of lithospheric plates, are mostly found in Earth's (1) crust (2) plastic mantle (3) outer core (4) inner core

53 What is the outermost structure in a plant cell? (1) cell membrane (2) cytoplasm (3) cell wall (4) chloroplast

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54 The vast variety of different traits found in humans results from (1) intensive training and education (2) sexual reproduction and mutations (3) exercise and conditioning (4) birth defects and recessive genes

55 Which factor has the least effect on a person’s metabolism? (1) exercise (2) hormones (3) intelligence (4) diet

56 If a species is no longer able to reproduce, it will (1) adapt to its environment (2) become immune to disease (3) become extinct (4) increase its population

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Base your answers to the following questions on the drawings of bird feet and the dichotomous key below.

57 Bird B is correctly identified as (1) a cormorant (2) a duck (3) an eagle (4) a jacana

58 What is a common feature of both the eagle and the kingfisher? (1) claws large (2) claws curved (3) three toes webbed together (4) four toes webbed together

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59 Which graph best represents the relationship between the amount of pollutants in the air and the quality of the air?

Answer is 3

60 The eyes of the owl and the rabbit shown in the diagram below give each animal a different advantage. The front-facing owl eyes allow the bird to accurately judge distance when swooping in on prey. The side-facing rabbit eyes allow the animal to detect the motion of possible predators.

The specialized eye types of these animals are examples of (1) disruptions of the natural balance (2) the interdependence of living things (3) adaptations for survival under certain conditions (4) involuntary responses to stimuli

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61 The energy obtained from food is measured in units called (1) watts (2) Calories (3) degrees (4) pounds

62 The diagram below shows a student making a wet-mount slide.

Why should the student make sure the edge of the coverslip touches the drop of water before setting the coverslip onto the slide? (1) to increase evaporation (2) to reduce air bubbles (3) to clean the slide (4) to prevent the coverslip from breaking

63 Beaver dams can cause floods. This statement shows how (1) animal growth is affected by environmental conditions (2) animal behavior may affect the environment (3) an animal’s health depends on its environment (4) an animal’s development depends on its environment

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Base your answers to the following questions on the diagram below. The diagram shows the offspring of a white mouse and a gray mouse. All of the offspring are gray.

64 Which is a correct gene combination for the parents shown in the diagram? (1) GG × GG (2) gg × gg (3) gg × GG (4) Gg × Gg

65 If two gray (Gg) mice mated, what percent of their offspring would have pure white fur? (1) 25% (2) 50% (3) 75% (4) 100%

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66 The diagrams below show the plant communities present in the same area at different times over a 200-year period following a forest fire.

What is the correct sequence of these plant communities following the forest fire? (1) B → A → D → C (2) B → C → D → A (3) B → D → C → A (4) B → A → C → D Base your answers to the following questions on the diagram below and on your knowledge of science. The diagram below shows some relationships within a natural community.

67 Which statement best explains the relationships shown? (1) Water changes over time to a nonrenewable resource. (2) Living things exchange materials with their environment. (3) Minerals recycle the dead materials in the environment. (4) Living things produce other living things.

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68 Which process produces oxygen that is released into the atmosphere? (1) respiration (2) locomotion (3) excretion (4) photosynthesis

69 Which graph best represents the relative distance between the particles of most substances in their solid, liquid, and gas states?

Answer is 1

Base your answers to the following questions on the chart below, which shows various data collected and predicted for Albany, New York, on March 9, 2001.

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70 The chart on the previous page shows information about Moon phases, times of sunrise and sunset, and (1) climate patterns (2) local weather conditions (3) seasonal changes (4) global warming

71 Which diagram correctly shows the position of the Moon with respect to Earth on March 9, 2001? **Use the chart on the previous page**

Answer is 3

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72 Which instrument dial shows a correct air pressure reading for Albany, New York, for this date and time? **Use the chart on the previous page**

Answer is 1

73 A chemical property of a mineral is evident if the mineral (1) breaks easily when struck with a hammer (2) bubbles when acid is placed on it (3) is easily scratched by a fingernail (4) reflects light from its surface

74 Four identical sand castles are shown below. Which sand castle will most likely be eroded fastest by the wind?

Answer is 3

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75 The diagram below shows a boulder rolling down a hill into a valley and then up the opposite hill.

At which position does the boulder have the greatest kinetic energy? (1) A (2) B (3) C (4) D Base your answers to the following questions on the graph below, which shows the solubility (amount that will dissolve in 100 grams of water) of three substances at various water temperatures.

76 Which statement is a correct interpretation of the data in the graph? (1) As water temperature increases, solubility decreases. (2) As water temperature increases, solubility increases. (3) As water temperature increases, solubility increases and then decreases. (4) As water temperature increases, solubility decreases and then increases.

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77 Use the diagram on the previous page. As the water temperature is increased from 30°C to 70°C, how many more grams of substance A will dissolve in 100 grams of water? (1) 20 g (2) 40 g (3) 50 g (4) 90 g

78 The diagram below shows a pinwheel rotating above a lit candle. The arrows indicate the direction of air flow.

Which energy transformation is best shown in this diagram? (1) heat to mechanical (2) mechanical to light (3) sound to heat (4) heat to sound

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Base your answers to the following questions on the diagrams below and your knowledge of science. The diagrams show liquid water changing to water vapor in four different situations.

79 Which observation would be evidence that the water is undergoing a phase change? (1) Waves form on the top of the pond. (2) Water soaks into the wet sand. (3) The water splashes out of the swimming pool. (4) The water level in the glass of water decreases.

80 How is heat energy transferred within the liquid water in the pond? (1) compound formation (2) convection currents (3) chemical reactions (4) nuclear reactions

81 The fur of a snowshoe rabbit changes to white during the winter. This change is an example of (1) adaptation (2) competition (3) metamorphosis (4) metabolism

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82 The drawing below shows a woodpecker using its long, sharp beak to obtain insects.

What factor might contribute to the extinction of this species of woodpecker? (1) a new source of food (2) an overabundance of trees (3) the use of pesticides in the forest (4) an increase in the population of insects

83 Which process gives rise to a variety of traits within a species? (1) sexual reproduction (2) dynamic equilibrium (3) cellular respiration (4) internal regulation Base your answers to the following questions on the diagram below, which shows many organisms in a food web.

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84 Use the diagram on the previous page. One type of organism in this web that represents a producer is (1) rabbits (2) grasses (3) trout (4) snakes

85 Which organisms obtain energy for growth and development directly from the Sun? (1) caterpillars (2) hawks (3) frogs (4) bean plants

86 According to this food web, which organisms are herbivores? (1) caterpillars (2) foxes (3) hawks (4) snakes

87 Which organism correctly completes the food web at A? (1) horses (2) mice (3) bacteria (4) trees

88 Fats are important nutrients because they (1) provide genetic information (2) contain stored energy (3) are used in photosynthesis (4) maintain bone density

89 Which factor contributes to global warming? (1) increased use of solar-powered cars (2) increased burning of fossil fuels (3) better long-term weather forecasts (4) changing distance between Earth and the Sun

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90 Oceans, glaciers, lakes, and rivers are part of Earth’s (1) atmosphere (2) hemisphere (3) hydrosphere (4) lithosphere

91 The diagram below shows the water cycle.

Which letter represents the process of evaporation? (1) A (2) B (3) C (4) D

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92 The graph below shows the solubility of two different chemical compounds.

Compared to copper sulfate, approximately how many more grams of potassium bromide would dissolve at 90°C? (1) 20 (2) 40 (3) 60 (4) 80

93 The diagram below shows the steps necessary to produce the energy needed to run a hair dryer.

As it moves from location A to location D in the diagram, the energy stored in the coal (1) is converted to solar energy (2) reduces the friction in the hair dryer (3) is recycled (4) is transformed

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94 The diagram below shows some ways in which groundwater can be affected by humans.

Which statement is best supported by the diagram? (1) Chemicals applied by farmers lower the level of pollution in drinking water. (2) Drinking water can become polluted from unsuspected sources. (3) Human activities do not affect groundwater. (4) Toxic waste is safe if buried below the level of the basements of nearby homes.

95 The pie chart below compares the amounts of energy from different sources used in the United States each year.

Which two energy sources together provide more than 50% of the energy needs of the United States? (1) nuclear and natural gas (2) hydropower and oil (3) oil and coal (4) natural gas and coal

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96 Which sequence of energy transformations occurs after a battery-operated flashlight is turned on? (1) electrical à light à chemical (2) electrical à chemical à light (3) chemical à light --. electrical (4) chemical à electrical à light

97 The gravitational force between two objects depends on the distance between the objects and each object's (1) mass (2) volume (3) pressure (4) temperature

98 Which diagram best represents molecules of matter in the solid phase?

Answer is 2

99 Which sequence correctly shows the relative size of the nine planets of our solar system?

Answer is 4

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100 The graph below shows the distance traveled by four cars, A, B, C, and D, over a period of time.

The average speed of a moving object can be determined by using the equation below.

Which car traveled at an average speed of 20 kilometers per hour?

(1) A (2) B (3) C (4) D

101 Surface winds on Earth are primarily caused by differences in (1) air density due to unequal heating of Earth’s surface (2) ocean wave heights during the tidal cycle (3) rotational speeds of Earth’s surface at various latitudes (4) distances from the Sun during the year

102 In humans, a trait can be determined by one pair or many pairs of (1) genes (2) microbes (3) cells (4) organs

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103 The density of Earth’s crust is (1) less than the density of the outer core but greater than the density of the mantle (2) greater than the density of the outer core but less than the density of the mantle (3) less than the density of both the outer core and the mantle (4) greater than the density of both the outer core and the mantle

104 Which map best represents the direction of surface winds associated with the high- and low-pressure systems?

Answer is 3

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105 The picture below shows a geological feature in the Kalahari Desert of southwestern Africa.

Which process most likely produced the present appearance of this feature? (1) wind erosion (2) volcanic eruption (3) earthquake vibrations (4) plate tectonics

106 Scurvy is a disease that sailors often got on long voyages. It was discovered that scurvy could be prevented by eating oranges and lemons. This suggests that scurvy is a disease caused by (1) exposure to sea air (2) a nutritional deficiency (3) a microorganism (4) lack of exercise

107 The diagram below shows the shadow cast by a telephone pole on March 21 at solar noon at a location in New York State.

Which shadow was cast by the same telephone pole on June 21 at solar noon? Answer is 2

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108 What is a disadvantage of using moving water to produce electricity? (1) Power is produced inexpensively. (2) Air pollution is produced. (3) Oil spills may occur. (4) The local ecosystem may be disrupted.

109 The photograph below shows deformed rock structure found on Earth’s surface.

Deformed rock structure like this is most often caused by (1) crustal plate collisions (2) deposition of sediments (3) extrusion of magma (4) glacial movement

110 The seismogram below shows the time that an earthquake P-wave arrived at a seismic station in Albany, New York.

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Use the seismogram on the previous page. If the earthquake occurred at exactly 10:00 p.m., approximately how far from the earthquake epicenter was Albany, New York? (1) 1,900 km (2) 3,200 km (3) 4,000 km (4) 5,200 km

111 On each topographic map below, the straight-line distance from point A to point B is 5 kilometers. Which

topographic map shows the steepest gradient between A and B? Answer is 4

112 In addition to oxygen, which gases make up the largest percentage of Earth’s atmosphere? (1) hydrogen, helium, and water vapor (2) hydrogen, methane, and ozone (3) carbon dioxide, water vapor, and nitrogen (4) carbon dioxide, methane, and helium

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113 The diagram below shows a method for determining a physical property of a mineral. The results are shown for two minerals, galena and calcite.

Which property of the galena and calcite is indicated by the color of the powder each leaves on the ceramic tile? (1) streak (2) hardness (3) reaction to an acid (4) reaction to a solvent

114 The diagram below shows tilted rock layers. The dashed lines represent missing parts of the rock layers.

Which process is most likely responsible for the removal of the missing parts of the rock layers? (1) erosion (2) deposition (3) earthquakes (4) faulting

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115 The data table below shows the mass of an 800-gram block of ice as it melts to a 600-gram block of ice.

Data Table

Time (minutes)

Mass of Block of Ice (grams)

0 15 30 45 60

800 750 700 650 600

If the current rate of melting continues, how many more minutes will be required for the 600-gram block of ice to reach a mass of 400 grams? (1) 15 (2) 30 (3) 45 (4) 60

116 In humans, a fertilized egg contains 46 chromosomes. Which bar graph best represents the number of

chromosomes contained in the sperm and egg before they united to make the fertilized egg? Answer is 2

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Although change in multicellular species usually takes thousands of years, some species of bacteria undergo major changes in just a few years. One reason for this difference is that these bacteria (1) are microscopic (2) do not contain DNA (3) reproduce very quickly (4) cause infectious diseases

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118 Competition is most likely to occur between which two organisms? (1) deer and butterflies (2) owls and bacteria (3) goldfish and rabbits (4) grass and strawberry plants

119 The illustration below traces the development of the corgi dog over several generations as a result of human activity.

This is an example of the human activity called (1) mutation (2) genetic engineering (3) selective breeding (4) natural selection

120 The graph below shows the number of known species in the five kingdoms of living things.

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Based on the graph on the previous page, which kingdom contains approximately twice as many known species as the Protista Kingdom? (1) Animalia (2) Plantae (3) Fungi (4) Monera

121 Note that this question has only three choices. Some microorganisms cause human disease. Other microorganisms are used in making cheese, yogurt, and bread. Based on this information, the relationship between humans and microorganisms can be (1) beneficial, only (2) harmful, only (3) beneficial or harmful

122 The diagram below shows the head structure of four different birds.

The birds’ beaks show how the birds (1) compete for the same food in their community (2) require different amounts of food for survival (3) store food for the winter months (4) are adapted to get food from different sources

123 The diagrams below show changes in a natural community over a period of 200 years.

Which process is illustrated in the diagrams? (1) ozone depletion (2) global warming (3) recycling resources (4) ecological succession