问题 单项选择题

在细水雾灭火系统的试验过程中,对于干式和预作用系统除要进行水压试验外,还需要进行气压试验,下列关于气压试验的说法中,正确的是()。

A.试验介质可以用氮气

B.双流体系统气体管道的试验压力应为水压强度试验压力的0.8倍

C.试验压力应为0.28MPa

D.在稳压24h后压力降不大于0.05MPa

答案

参考答案:D

解析:不大于0.01MPa

阅读理解

B

People have strange ideas about food. For example, the tomato is a kind of very delicious vegetable. It is one of useful plants that can be prepared in many ways. It has rich nutrition and vitamin in it. But in the 18th century, Americans never ate tomatoes. They grew them in their gardens because tomato plants are so pretty. But they thought the vegetable was poisonous (有毒的). They called tomatoes “poison apples.”

President Thomas Jefferson, however, knew that tomatoes were good to eat. He was a learned man. He had been to Paris, where he learned to love the taste of tomatoes. He grew many kinds of tomatoes in his garden. The President taught his cook a way for a cream of tomato soup. This beautiful pink soup was served at the President’s party. The guests thought the soup tasted really good. They never thought their president would serve his honored guests poison apples. Jefferson never spoke to his honored (忠实的) guests about the fact.

46. After you read the passage, which of the following do you think is true?

A. Americans never ate tomatoes after they began to plant them.

B. Americans didn’t eat tomatoes before 19th century.

C. Even now Americans don’t eat tomatoes.

D. In the 18th century Americans ate a lot of tomatoes.

47. The passage tells us that Jefferson was a President who learned to love the taste of tomatoes       .

A. while he was in Paris           B. when he was a little boy

C. because his parents told him so   D. from books

48. According to the text, _______ made the beautiful pink soup served at the President’s party?

A. the President himself        B. a French cook

C. the President’s cook         D. the President’s wife

49. From the passage we know all the honored guests invited by Jefferson were      .

A. people from other countries           B. from France

C. people of his own country             D. men only

50. According to the passage, which of the following is NOT true?

A. All of the guests knew the soup that was served at the President’s party was made of tomatoes.

B. All of the guests thought the soup which was prepared by the President’s cook was nice.

C. All of the guests thought the taste of the beautiful pink soup was nice.

D. None of the guests knew that their president would serve his honored guests poison apples.

单项选择题