Astronomers want to make maps of the sky showing sources of X-rays or gamma rays. Explain why those X-rays and gamma rays must be observed from above Earth's atmosphere.

Explanation:

These electromagnetic waves have a very small  wavelength, smaller than air molecules, hence are highly prone to interference by the atmosphere when observed from the earth’s surface.  Therefore there would be huge distortions to the signals carried by these waves hence rendering them unsuitable for studying space. This is why it is needed that satellites that study in the X-ray and gamma rays spectrum of electromagnetic waves are launched into space. On the other hand, examples of electromagnetic waves with relatively longer wavelength to pass through the atmosphere with little or no interruption is microwave and radio waves.

d. air pressure decreases as altitude increases.

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