Heat
a. is a measure of energy
b. cannot move through a vacuum
c. is the internal energy of matter
d. is the same as temperature

The answer is C, is the internal energy of matter.

Explanation:

All matter is made of atoms and molecules. These particles are always in motion, whether it is a slow vibration or a rapid movement. The internal motion of matter is a type of energy called heat. In other words, heat is the kinetic energy of matter.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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