ANSWER SECTION C

10. (a) hypothesis : The time taken for the thumbtack to fall for metal/iron is shorter than non metal // Metal / iron is good thermal conductivity compare to non metal. (1m)

(b) i) Aim: To study the thermal conductivity between metal and non-metal. (1m) ii) variables: MV: metal and non-metal //type of substance// type of rod. RV: The time taken for thumbtack to fall// thermal conductivity. CV: Size of rod//the distance between thumbtack and bunsen burner.

(any TWO : 2m) iii) Apparatus: A stop watch (1m) iv)procedure: 1. Stick the thumbtack to the iron rod using wax // diagram. (1m) 2. Heat one of the iron rod using bunsen burner//diagram. (1m) 3. Record the time taken for the thumbtack to fall using stop watch. (1m) 4. Repeat the experiment using glass rod. (1m) v) Data:

(1m) Total :10m

11. a) Alloy Pure metal

Strong Weak 1m

Resistance to corrosion Easy to corrode 1m

Better shiny and beautiful appearance

Shiny 1m

Hard Malleable 1m

4 m

b)

Two common characteristic

1. Strong 2. Resistance to corrosion

1m

1m

Initial concept Strong and resistance to corrosion are initial concept for an alloy

1m

Type of rod Thermal conductivity// time taken for thumbtack to fallMetal//iron rodNon-metal// glass rod

Other example and non-example

Other example for an alloy is medal and non-example for an alloy is iron nail.

1m1m

Actual concept An alloy are strong, resistance to corrosion and hard. 1m

6m

Total: 10m

12. (a) i) Type drug : a) stimulants b) depression c) hallucinogens d) anti-depressants e) inhalants *Accept if the student gives examples of the drugs. (2m) ii) risk taking drug: 1. Become irritable and lose interest in their friends, hobbies and work 2. Drugs addicts turn into crime to get money for drugs. (Accept any reasonable answer) (2m)

(b) Identify the problem: (1m) Baba is stealing to get some money to buy drugs.

Clarification of the problem: (1m) Because of drugs addicted Baba will do anything including stealing to get some money to buy drugs.

Solving Method: (3m) • Try to get traditional treatment for his son. • Register his son to a rehabilitant center. • Always control the activities done by his son

Best method & explanation (1m) Register his son to a rehabilitant center because he will get treatment that include all aspects of life and thus solve the Problem. Total: 10m