The nucleus of an atom consists mainly ofa) neutrons and electronsb) protons and electronsc) protons and neutronsd) protons, neutrons, and electronse) none of the above

Protons and neutrons

Explanation:

The nucleus is the most massive part of an atom. It is made up of neutrons and protons. Protons are positively charged while the neutrons have no charge. Both the proton and neutrons are known as nucleons because they are found in the nucleus.

The mass of an atom is concentrated in the nucleus due to the masses of the nucleons compared to the electrons in the orbitals. Electrons occupies more atomic space compared to the nucleons.

b. atoms in metallic solids are not arranged in a regular pattern

explanation:

a rain shadow is a dry region of land on the side that is protected against the prevailing winds of a mountain range. the prevailing winds are the winds that occur most of the time in a particular place of the earth

prevailing winds carry air toward the mountain range. as the air rises up over a mountain range, the air cools, water vapor condenses, and clouds form. on this side of the mountains, called the windward side, precipitation falls in the form of  rain  or snow. this dry air produces a  rain shadow.