A. attract each other.
The Law of Universal Gravitation discusses the phenomenon of gravity. Remember that gravity is the force that keeps us on Earth; the Earth pulls us down, and our bodies pull back. Gravity is the force of attraction, so the correct answer is a).
Answer:
Explanation: This is done using the equation:

Because the Radius is a know value. We have the following.

Which is:
4188.7902 mm
Answer:
When all the electrons are removed from an atom, it becomes something as a positively charged particles also known as alpha particles.
<u>Explanation:
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The bare nucleus which is positively charged help in scattering experiments as it has high penetrating powers. <em>An atom is made up of electrons, protons and neutrons. We need huge energy to separate the electrons from their parent atom, still making it separated brings you a particle with a positive charge and only mass having high penetrating power.
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