4. It is still necessary for human pilots on the ground to control such a plane because________.
A. such a plane is no more than an unmanned aerial vehicle
B. the virtual pilot cannot handle an emergency
C. human pilots can make more money for this
D. there is a datalink connection to the controls
查看答案
5.Which of the following can serve as a proper title for the passage?
A. The New Kind of Traveler
B. The Fully Automated Airplane
C. The Virtual Pilot
D. The Removed Human Pilot
6. What is NASA trying to do?
A. To make carbon nanotubes.
B. To protect astronauts from ions
C. To make a new discovery
D. To build a super spaceship
7. Carbon nanotubes could be used to make the skins of spacecraft because____.
A. they are much lighter than metal
B. they are 600 times stronger than steel
C. they can shield the spacecraft from radiation
D. they can break ions in space rays
8.What will happen when ions hit the metal on a spaceship?
A. Some worse radiation will be produced.
B. All radiation will be blocked out.
C. The metal on the spaceship will break up.
D. The ions will move at high speeds.
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