Hỗn hợp X gồm ancol metylic, etylen glicol. Cho m gam X phản ứng hoàn toàn với Na dư, thu được 2,24 lít khí H₂ (đktc). Đốt cháy hoàn toàn m gam X, thu được a gam CO₂. Giá trị của a là: 

A. 8,8

B. 2,2.         

C. 6,6.

D. 4,4.

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

Your brother hardly talks to anyone, _____________ ?

A. does he

B. is he

C. doesn’t he

D. isn’t he

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

Only after she had finished the course did she realize she _____________ a wrong choice.

A. had made

B. has made

C. had been making 

D. was making

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

What is the main idea of the passage?

A. Today’s style of American music is mostly influenced by African-rooted songs

B. It is hard to exactly recognize the people who started the American musical tradition

C. Spirituals, blues and ragtime are the major components that formed jazz

D. American’s musical history was built by several famous musicians

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

Flash photography is _____________ prohibited in this museum.

A. rigorously

B. strictly

C. staunchly

D. firmly

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

He was _____________ from the competition for using drugs.

A. disqualified

B. omitted

C. sacked

D. prevented