Câu 28: Hai dây nhôm có chiều dài bằng nhau, dây thứ nhất có tiết diện gấp đôi dây thứ hai. Tỉ số  là

A. .                B. .                                      C. .                      D. .

III. Tick  [ü] in front of correct sentences and [X] in front of incorrect ones and correct them.

_____  1    We have already worked up a new way of doing it.

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_____  2.   Jim wants to be a successful writer when he grows out.

                  _____________________________________________________________________

_____  3.   We are looking forward to hearing from you soon.

         _____________________________________________________________________

_____  4.   I can’t keep up to all the changes in technology nowadays.

                  _____________________________________________________________________

_____  5.   The nearby shop will be closed up next month.

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_____  6.   The team scored another goal and made sure about championship.

                  _____________________________________________________________________

_____  7.   Last year a research on the consequences of water pollution was carried on.

                  _____________________________________________________________________

_____  8.   Jim has come up with a brilliant idea to tackle the problem.

                  _____________________________________________________________________

_____  9.   Have you ever considered getting rid your bad habits?

                  _____________________________________________________________________

_____  10. The teacher asked us to see through the textbook before she continued.

1.   This singer will _________________ a new album this year.