What refers to the amount of a substance in a given space

An atom of nitrogen had seven protons in its nucleus. how many electrons does it have

Pl which diagram illustrates prophase?

Identify characteristics of energy from the sun. check all that apply. almost all of the energy on earth comes from the sun. energy from the sun is known as mechanical energy. the energy in fossil fuels originally came from the sun. plants convert the energy of sunlight into chemical energy.