How many different kinds of atoms do occur naturally on earth? Why do you think so?

An animal cell loses the ability to convert energy stored in food to energy that the cell can use. which of the cell's organelles has stopped working? a. the mitochondria b. the nucleus c. the vacuoles d. the endoplasmic reticulum

Salt in oceans comes from and of rocks

Concentrations expressed as a percent by mass are useful when the solute is a a. liquid b. gas c. solid