The best title for the text should be______.
A. The Outer Space
B. The CubeSail
C. Accidental Collisions
D. Sweeping the Skies
查看答案
What is the main idea of the text？
A. Recycling of electronic items is a "success story".
B. Environmentalists are opposed to recycling electronics.
C. Recycling can not keep pace with electronics sales.
D. It is unnecessary to recycle electronics.
Which one is NOT the application of the system designed by Vaios Lappas？
A. To halt creating more space junk.
B. To remove the satellites at the end of their useful lives.
C. To stop the accidental collisions in space.
D. To clean the junk created by dead satellites.
Orbits decay due to ______.
A. the acceleration of the spacecraft
B. the crash with small amounts of air molecules
C. the invention and application of solar sails
D. the existence of air molecules
Which one of the following is NOT the efforts people have made？
A. Vermont has enacted a law to demand e-waste recycling.
B. Many companies join in the program to promote electronic recycling.
C. Some companies pay for used gadgets to resell or recycle.
D. Best Buy puts boxes in every store to collect e-waste.
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