问题 问答题

星期六,爸爸开车带小李去新华书店买科普读物,回来后小李向爸爸请教了有关车的一些问题,并做了记录,内容如下表所示.请你根据小李记录的内容计算:

 平均车速 30km/h
 等速耗油 9L/100km
 油价 6.10元/L
 汽油(93#)密度 800kg/m3
(1)小李去新华书店单程时间30min,则小李家距新华书店的路程大约是多少千米?

(2)往返路程中,用掉汽油多少千克?

(3)此次行程需花费汽油费多少元?

答案

(1)小李家距新华书店的路程S=Vt=30km/h×

h
2
=15km.

答:小李家距新华书店的路程是15km.

(2)用掉汽油的体积V=2×15km×9L/100km=2.7L=2.7×10-3m3

汽油的质量m=ρV=800kg/m3×2.7×10-3m3=2.16kg.

答:往返路程中,用掉汽油2.16kg.

(3)汽油费:6.10元/L×2.7L=16.47元.

答:此次行程需花费汽油费16.47元.

阅读理解

阅读理解。

     Which country grows the most tea? The answer is India.  It grows three times as much as China. Which country drinks the most tea? It's neither China nor Japan. It's Great Britain.

     In the wild, tea plants may be 30 feet tall. But a plant grown for market is pruned(修剪).Pruning keeps the plant only three or four feet tall. This is an easy height for tea picking. Only the two top leaves of each

new shoot(芽)are picked. So to make money, tea plantations must be huge.

     In general, there are two kinds of tea, black tea and green tea. They are made in different ways. When black tea is made, it loses nearly all of its healthy qualities.  But green tea retains its healthy qualities. For

instance, it may prevent heart disease(病).

     How did we get tea bags? The answer: by accident. People used to send tea in tin boxes.  This was

expensive. Someone thought of a cheaper way. He sent tea in small silk bags. Customers would open the bag. They would put the leaves into a pot as usual. One customer put the bag into a pot. Then he just

poured hot water over it. And the tea bag was born.

     Shen Nong was the first to drink tea. This was about 2737 B.C.Shen was ill, so he drank several cups of hot water daily. One day something happened.  Leaves from a wild tea tree fell into the hot water pot.

The next cup was poured. The water was now colored. Shen tasted it.  He liked it.  He drank it all. Shen was proud of his new drink. He served it to his guests. World spread. People thought this way. Tea is

good enough for the emperor. So it must be good enough for the people. Tea became the drink of China.

1. The best title for this passage might be______.

A. An Ancient Drink

B. Green Tea

C. A Favorite Drink for Centuries

D. Tea Plant

2. The author's main purpose in writing this passage is to______.

A. persuade you

B. make you laugh

C. tell you how to do something

D. give you information

3. In this passage "retains" means "______".

A. keeps

B. makes

C. takes

D. loses

单项选择题