Cleaner air, litres of water and a filter
Answers are for parents and teachers.
1
List three sources of energy that do not burn fuel and write where one of them is used in Egypt.
For example: wind (Zafarana), the Sun (Benban near Aswan), falling water (Aswan High Dam).
2
A leaking tap loses 3 L every hour. How much water is that in 8 hours? How much in a whole day of 24 hours?
3 × 8 = 24 L; 3 × 24 = 72 L.
3
A family of 5 each takes a 4-minute shower at about 10 L every minute. How many litres is that? How many would they save if each showered 1 minute less?
5 × 4 × 10 = 200 L. With 3 minutes: 5 × 3 × 10 = 150 L. They save 50 L.
4
Make a poster with three tips for saving water at home. Show one number that proves a tip works.
Answers differ, for example: turn off the tap while brushing, saving about 15 L each time.
5
Write a claim, evidence and reasoning to answer: why can water that looks clear still be unsafe?
Claim: clear water can still be unsafe. Evidence: a filter only holds back bits you can see. Reasoning: germs and dissolved things are too small to be caught or seen.