Answer:

Explanation:
-The chemical formula for Molybdenum (V) Dichromate is 
-There are 21 moles of oxygen per one mole of Molybdenum (V) Dichromate
-We apply Avogadro's constant to find the number of atoms of oxygen:

Hence, there are
Answer:
the difference of electrical potential between two points.
Explanation:
"Gamma rays" is the name that we call the shortest of all electromagnetic waves. They're shorter than radio waves, microwaves, infrared waves, heat waves, visible light waves, ultraviolet waves, and X-rays. They extend all the way down to waves that are as short as the distance across an atom.
Being so short, they carry lots of energy. They can penetrate many materials, and they can damage living cells and DNA. They're dangerous.
The sun puts out a lot of gamma radiation. The atmosphere (air) filters out a lot of it, otherwise there couldn't even be any life on Earth.
As soon as astronauts fly out of the atmosphere, they need a lot of shielding from gamma rays.
You know the precautions we take when we're around X-rays. The same precautions apply around gamma rays, only a lot more so.
It's only in the past several years that we've learned how to MAKE gamma rays without blowing things up. Also, how to control them, and how to use them for medical and industrial applications.