Các tỉ số sau đây có lập thành tỉ lệ thức không?

a) 3 5 : 6  và  4 5 : 8 ;               b) 2 1 3 : 7  và 3 1 4 : 13 .

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

Smoking is an extremely harmful habit. You should give it up immediately.

A. When you give up smoking immediately, you will affect your health with this harmful habit

B. Stop your smoking immediately so it will become one of your extremely harmful habits

C. You should give up smoking immediately and you will fall into an extremely harmful habit

D. As smoking is an extremely harmful habit, you should give it up immediately

Mark the letter A, B, C, or D on your answer sheet to indicate the sentence that best combines each pair of sentences in the following questions.

He behaved in a very strange way. That surprised me a lot.

A. What almost surprised me was the strange way he behaved

B. He behaved very strangely, which surprised me very much

C. His behavior was a very strange thing, that surprised me most

D. I was almost not surprised by his strange behavior