1. Predict what will be observed after five days.
Fish in tank U: They are still alive.
Fish in tank V: Both will die.
2. Give a reason (inference) for your answer in 3(a)
Fish in tank U: They are alive because they get enough food and air.
Fish in tank V: They die because they do not get enough air.
3, What is the conclusion of the investigation?
Air is the basic need of living things.
