Fundamental substances that cannot be broken down chemically into simpler subsances
a) elements
b) ions
c) bonds
d)electrons

A. Elements

Elements are substances that cannot be separated into simpler substances. Salt is made up of the elements sodium and chloride. Water is made up of the elements hydrogen and oxygen, to list a few.

8 m/s because for him to get the same amount of energy as ray is putting out, bobby, who weighs half as much as ray, needs to run twice as fast.