một hình hộp chữ nhật có chiều dài 9dm , chiều rộng 4dm , chiều cao 5dm. một hình lập phương có cạnh bằng trung bình cộng số đo của ba kích thước của hình hộp chữ nhật trên. Tính:                                                                                                                           a) thể tích của hình hộp chữ nhật .                                                                                     b) thể tích của hình lập phương.
Giúp mình với ạ!
 

Choose the word or phrase (A, B, C or D) to complete the following sentences.

21. She is tired_______ getting up early.

            A.with                        B.in                             C.of                             D.to

22. These schools look so old. They________ in 1997.

            A. built                       B. are built                C. were built             D. have built

23. Are you proud________ your country and its tradition?

            A. about                     B. on                           C. of                         D. for

24. The film is about the sinking of ship Titanic on its first ………. .

A. journey                 B. trip                         C. excursion              D. voyage

25. My English is far from perfect but I know enough to get ……….

A. in                           B. with                                   C. by                           D. over

26. The Temple of Literature                       in 1070.

A. find                        B. found                     C. was found             D. was founded

27. The US is a ………. country with over 80 ethnic groups.

A. bi- lingual                         B. rich                        C. ethnic                    D. multi-cultural

28. If he  ________ working on his report, he’ll have finished it by tomorrow.

A. keeps                     B. kept                        C. is keeping             D. has kept

29. No one can do it well and ____________.

            A. so can she             B. neither can she     C. she can’t, too        D. she can, either

30. Hydro and nuclear power can ………. a great deal of energy. They are renewable and plentiful.

A. make                     B. create                    C. do                           D. generate

31. Great Heart Charity is a ______ organisation. They do not work for money.

A. profitable             B. non-profit             C. community           D. common

32. A_____is a person who plays a musical instrument or writes music, especially as a job.

A.poet                        B. singer                    C. comedian              D. musician

33. Many kinds of fruits and vegetables ______ at the floating market in Can Tho. 

            A.sell                        B. will sell                 C. are sold                 D. are selling

34. I don’t like so much noise so loud pop music really is not my ………. .

A. thing                      B. job                         C. task                                    D. work

35. Don’t call Dr Smith at 9 a.m tomorrow. He  ………. a lecture then.

A. will have               B. is going to have   C. will be having      D. is having

36. We all enjoyed the play so much that we ___________ for ten minutes.

            A.smiled                    B.screamed                C.cried                       D.applauded

37. The group is___________ for their albums and tours around the world.

A. well-prepared      B.well-known           C.well-know              D.know-how

38. ______, he walked to the station.

  A. Despite being tired                                   B. Although to be tired

  C. In spite being tired                                   D. Despite tired

39. Because his speech was so confusing, ………. people understood it.

A. few                        B. clever                    C. less                        D. many

40. A. Wake up and let’s go out.                B. ……… . I think, I’ll stay at home and read books.

A. No, count me out. B. No, count me on. C. No, get me out.   D. No, get me on

Tổng của hai số bằng 120.
a) Tìm hai số đó, biết rằng nếu gấp số bé lên 4 lần thì được số lớn.
b) Tìm hai số đó, biết rằng nếu giảm số lớn đi 5 lần thì được số bé