Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.

His business is growing so fast that he must take _____ more workers.

A. up

B. over

C. on

D. out

N số hạng là:

(n+1).n=378.2=756=27.28=n=27

tick bạn

Có thể thu được bao nhiêu anken đồng phân (kể cả đồng phân hình học) khi tách HBr ra khỏi các đồng phân của  C 4 H 9 Br

A. 3

B. 4

C. 5

D. 6

Mark the letter A, B, C or D on your answer sheet to indicate the word of phrase that is CLOSEST in meaning to the underlined part in each of the following question.

John, could you look after my handbag while I go out for a minute

A. take over          

B. take care of       

C. take part in       

D. take place

a) A= \(\dfrac{4}{7}+\dfrac{3}{4}+\dfrac{2}{7}+\dfrac{5}{4}+\dfrac{1}{7}\)

= \(\left(\dfrac{4}{7}+\dfrac{2}{7}+\dfrac{1}{7}\right)+\left(\dfrac{3}{4}+\dfrac{5}{4}\right)\)

= \(\dfrac{4+2+1}{7}+\dfrac{3+5}{4}\)

= \(\dfrac{7}{7}+\dfrac{8}{4}\) = \(1+2\) = \(3\)

b) B= \(\dfrac{-4}{12}+\dfrac{18}{45}+\dfrac{-6}{9}+\dfrac{-21}{35}+\dfrac{6}{30}\)

= \(\dfrac{-1}{3}+\dfrac{2}{5}+\dfrac{-2}{3}+\dfrac{-3}{5}+\dfrac{1}{5}\)

= \(\left(\dfrac{-1}{3}+\dfrac{-2}{3}\right)+\left(\dfrac{2}{5}+\dfrac{-3}{5}+\dfrac{1}{5}\right)\)

= \(\dfrac{\left(-1\right)+\left(-2\right)}{3}+\dfrac{2+\left(-3\right)+1}{5}\)

= \(\dfrac{-3}{3}+\dfrac{0}{5}\) = \(-1+0\) = \(-1\)