a: k=3/8

b: y=3/8x

4 going to buy a lot of things for the party tomorrow

5 is go out somewhere for a drink

6 Jane going to travel around the world

7 short and fair

8 a good football player

9 a fast runner

10 hard workers

11 swim well

12 worked busily

1 A

2 D

3 C

4 A

5 A

1 C

2 A

3 D

4 A

5 B

6 D

7 C

8 C

II

1 A

2 B

III

1 deaf

2 countless

3 inventor

4 delivery

IV

1 He worked with deaf-mutes at Boston University in America

2 I am going to see the movie Dream city at 6.45 this evening

V

1 going to visit my friends next Sunday

2 go to the movie tonight

hơi nhiều chút nhưng thôi cố làm vậi =((

8. careful enough to do that job.

9. going to come over to pick you up.

10. going to visit her grandparents tomorrow.

11. not going to buy some new books.

12. to play basketball this afternoon.

13. going to do tomorrow?

    cấu trúc nè :3 intend to V = be going to V

14. to visit our teacher today.

15. to finish this homework now.

16. take care of her house.

17. to go home on time.

18. to ask my aunt and she's downstairs.

19. about coming to my house for lunch?

20. we meet inside the center, at the cafe corner?

Câu 1.

Khi mở khóa K:

\(I_m=I_1=0,4A\)

Khi đóng khóa K:

\(I_m=I_1+I_2=0,6\Rightarrow I_2=0,2A\)

\(U_1=0,4\cdot5=2V\)

\(\Rightarrow U_2=U_1=2V\)

\(\Rightarrow U=U_1=U_2=2V\)

\(R_2=\dfrac{U_2}{I_2}=\dfrac{2}{0,2}=10\Omega\)