Why does pressure vary in the atmosphere

Pressure varies in the atmosphere because air molecules are being pulled down towards the center of the earth-hope this helps!

Any photo? or something

Because electrons have negligible mass, to account for the mass of the isotope, there must be 16 neutrons, 16 neutrally charged, massive, fundamental particles present in the sulfur nucleus. and thus finally, if we have the 32s2− ion, there are 18 electrons, 16 protons, and 16 neutrons.