Diện tích xung quanh bể cá là:
 (6 + 4) x 2 x 5 = 100 (cm²)
Diện tích đáy bể cá là:
 6 x 4 = 24 (cm²)
Diện tích kính dùng làm bể cá đó là:
 100 + 24 = 124 (cm²)
        Đáp số : 124 cm²

Đổi : 15 phút = 0,25 giờ
Quãng đường người đó đi trong 0,25 giờ là:
 12 x 0,25 = 3 km
           Đáp số : 3km

1. I like milk, meat and cola.
2. He plays badminton in the morning.
3. We go to bed at midnight.
4. My mom does housework on weekends.
5. The train arrives at 8.00 a.m.
6. My elder sisters finish works at 7 p.m.
7. Ann’s friends live in a big house.
8. The dog likes her, not me.
9. Emma doesn't study on weekends.
10. He has a new shirt today.
11. I usually have dinner  at 6.40 p.m.
12. James doesn't study very hard, so he never gets high scores.
13. My father often teaches me Math on Saturday evenings.
14. I like English and she likes Korean.
15. My sister goes out every day.
16. We don't have breakfast every morning.

1. had built
2. hadn't been
3. had already done
4. had made
5. had put on
6. hadn't ordered
7. had learnt
8. had fallen
9. Had he phoned
10. had ridden
11. had gone
12. had left
13. hadn't cleaned
14. Had they studied
15. hadn't eaten

7. B
8. 3/4

B

1. A
2. D
3. C
4. A
5. D
 

B

52,8 x 24 + 52,8 x 1 + 52,8 x 75
= 52,8 x (24 + 1 + 75)
= 52,8 x 100
= 5280