20. How is the retina of a human eye similar to the film of a camera?
21. How are seeds of a mango dispersed?
22. Which method would you use to find the volume of an irregular object?
23. How is the respiration of a tadpole similar to that of a fish?
24. Peter used water to put out a fire caused by petrol but the fire continued burning. Suggest one thing he should have used to put off the fire.
25. Musa is long- sighted. Draw the type of lens he should use to correct his eye problem.
26. Give any one reason which shows that animal and plants depend on each other.
27. Why is it difficult to control poultry disease in free-range system?
28. How does a tortoise protect itself against its enemies?
29. Why are bacteria in rotting rubbish very useful to man?
30. Give one reason why mercury is used in thermometers instead of water.
31. Give the difference between freezing and condensation.
32. Give the difference between the way man and insects breathe.
33. When it is said that Badru is anaemic, what is lacking in his blood?
34. State one disease that both a passive and active smoker may suffer from.
35. Why does blood go to the lungs before it is pumped out to all parts of the body?
36. Find the density of an object whose mass is 10g and volume is 5cm3.
37. Give one reason why a bat is a mammal not a bird.
38. Give one way in which the sun is important to plants.
39. Give one reason why drugs should be prescribed by health workers before they are used by sick people.
40. How is an echo similar to an image?