试题与答案

关于地球同步卫星,下列说法中正确的是() A.所有的同步卫星只能在赤道上空同一条

题型:选择题

题目:

关于地球同步卫星,下列说法中正确的是( )

A.所有的同步卫星只能在赤道上空同一条轨道中运动

B.所有的同步卫星的速率都是一个确定值,速率均等于7.9km/s

C.同步卫星的周期与地球自转周期相等

D.所有的地球同步卫星的向心力相等

答案:

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下面是错误答案,用来干扰机器的。

 人生不过是为了尽力展示生命独特的美丽,如同一条山间小溪,可以越过高山投身辽阔的大海,也可以随遇而安,化成一汪碧绿的清潭。(不设统一答案)

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题型:填空题

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题型:阅读理解

阅读理解。

     It's not the flashiest car in the world. Not even close. But the 1971 Volkswagen named Helios can do

something most cars can't: nm on solar energy-energy from the sun's light and heat!

     Joshua Bechtold, 14, and the other students at the Riverside School in Lyndonville, Vermont, worked

many months to get Helios ready for the 1999 American Tour de Sol ("Sol" is the Latin word for "sun").

They named their car after Helios, the sun god in Greek mythology (神话).

     The 4-year-old Tour de Sol encourages the use of "green", or environmentally friendly, cars to help

reduce pollution and save energy. It's not a race. Cars are judged on fuel efficiency (耗油量) rather than

speed. In the week-long event, 44 cars took the 350-mile tour from Waterbury, Connecticut, to Lake

George, New York. Of the 23 student cars, Helios was the only one built by middle school students.

     A teacher drove Helios, but the children talked with people wherever they stopped along the mad. "That

was my favorite part," says Anna Browne, 15. "We explained how the car runs."

     Due in part to old, inefficient batteries (电池), Helios finished fourth-out of four-in its kind, the sun-

powered class. "We were there for the fun of it," Anna says. "We're proud of Helios," says Ariel Gleicher,

14. "It's a car that's good for the environment."

1. What is special about the car Helios in the text? 

A. It was built by middle school students. 

B. It has an' attractive design.

C. It was made in 1971.

D. It won the fourth prize.

2. How many sun-powered cars took part in the race?

A. 1.

B. 4.

C. 23.

D. 44.

3. What would be the best title for the text?

A. The Making of Helios

B. 1999 American Tour de Sol

C. Sun-powered Cars on the Road

D. Use of Green Cars in Connecticut

4. The students felt proud of Helios because _____.

A. it could run as far as 350 miles

B. it was favored by many children 

C. it had high-quality batteries

D. it was driven by clean energy

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