Phản ứng nào sau đây dùng để điều chế anđehit axetic trong công nghiệp:

A.  C H 3 − C ≡ N → H 2 O / H + C H 3 C H O

B.  C H 3 − C H 2 O H → K 2 C r 2 O 7 / H 2 S O 4 C H 3 C H O

C.  C H 3 − C H 2 − O H → K M n O 4 / H 2 S O 4 C H 3 C H O

D.  C H 2 = C H 2 + O 2 → P d C l 2 ,    C u C l 2 C H 3 C H O

Mark the letter A, B, C, or D on your answer sheet to indicate the word CLOSEST in meaning to the underlined word in each of the following questions.
The works of such men as the English philosophers John Locke and Thomas Hobbes helped pave the way for academic freedom in the modern sense.

A. terminate

B. prevented

C. enhanced

D. incorporated

Jim: “Did you enjoy your graduation ceremony?”
Linda: “Oh yes, I didn’t like__________ all the time, though.”

A. being photographed                       

B. it to be photographed

C. to have been photographed             

D. photograph

Daisy has such many things to do that she has no time to go out.

A. has                            

B. to do                

C. to go                

D. such

Mark the letter A, B, C, or D on your answer sheet to indicate the word that differs from the other three in the position of primary stress in each of the following questions.

A. attitude

B. attention

C. determine

D. atomic

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