2.fishes
3.strawberries
4.knives
5.radios
6.buses
7.apples
8.glasses
9.babies
10.dishes
11.feet
12.toys
13.leaves
14.sanwiches
15.boxes
16.people
17.deers
18.oxes
19.women
20.butterflies
21.teeth
22.mice
23.kangaroos
24.children
25.giraffes
26.chefs
27.gooses

a) B(12) | x < 100 = \(\left\{12;24;36;48;60;72;84;96\right\}\)
b) Ư(20) | x < 8 = \(\left\{1;2;4;5\right\}\)
a) B(8) = \(\left\{16;24;32;40;48;56;72;80;88;96;107;115\right\}\)
b) Ư(45)| x > 5 = \(\left\{9;45\right\}\)

12= 2² . 3
21= 3.7
28= 2².7
➜ 2².3.7 = 84
B(84)= \(\left\{84;168;252;336;420;...\right\}\)
vì x < 500 nên
x ϵ \(\left\{84;168;252;336;420\right\}\)

1.paint
2.have
3.plays
4.reads
5.studies
6.go
7.doesn't do
8.is
9.doing
10.sweeps

1. works
2. likes
3. lives
4. rains
5. flies
6. closes
7. tries
8. passes
9. is / watch
10. writes
11. speaks
12. doesn't live

Body: head, eyes, nose, mouth, ears, hand, arm, fingers, foot, toes
Public places: Park, Bank, museum, zoo, stadium, library, restaurent
Means of transport: plane, car, train, bus, ship
Daily activities: get up, brush teeth, take a shower, have breakfast

a) 50
b) 71

1.Job
2.He
3.students
4.To
5.learn
6.question 
7.Answer
8.good

hình như là Cánh Diều ạ, mình cũng k chắc