Two adams of the same element with different mass numbers are called?

neutrons
electrons
isotopes
nuclei

The tilt of the earth's axis of rotation is responsible for the a) ocean's tides. b) size of the moon. c) brightness of stars. d) earth’s seasons.

Although respiratory organs vary across different organisms, they all contain respiratory surfaces that have a large surface area and are extremely thin. explain why having an extremely thin respiratory surface with a large surface area is advantageous for the process of gas exchange

Which of the following is a physical property flammability heat of combustion solubility and toxicity