Official 19 Lec 2
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Question 5 of 6
According to the professor, why do radio astronomers sometimes have difficulty studying very distant objects?

A.

Signals from closer objects interfere with radio waves from space

B.

Particles in the atmosphere change the direction of radio waves

C.

Radio waves from space are not very strong

D.

Light waves from sources on Earth alter radio waves from distant objects

我的答案:

正确答案:AC

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