Earth's atmosphere blocks short wavelengths of the electromagnetic spectrum. Which telescopes must be places in orbit around Earth in order to observe short-wavelength radiation?

gamma-ray telescopes

Explanation:

this is the answer because the question is asking what telescope must be

placed to observe SHORT-WAVELENGTH radiation. Gamma-rays have very short wave-lengths so therefore it would be gamma-ray telescopes. visible, infrared, and radio all have long wave-lengths, so we can instantly eliminate them.

the atomic number will stay the same no matter how many electrons it has, so it doesn’t decrease nor increase. it’ll only change with a different number of protons

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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