in an electrically neutral atom of any element, there are equal numbers of

a)protons and neutrons. b)electrons and protons. c)electrons and neutrons. d)atomic number and atomic mass

B) Electrons and protons  

Explanation:

Each proton has a positive charge, and each electron has a negative charge. If the atom is electrically neutral, there must be the same number of electrons and protons.

A) and C) are wrong. Neutrons have no charge, so they can't counteract that of the protons or the electrons.

D) is wrong. The atomic number is the number of protons, and the mass number is the number of protons plus neutrons. The neutrons can't  counteract the charge of the protons,

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.