Answer:
I believe it's cirrus clouds.
Explanation:
A measure of the number of particles of a substance in a given volume would be concentration. <span>In chemistry, </span>concentration<span> is the abundance of a constituent divided by the total volume of a mixture. There are a number of ways expressing it such as molarity, molality, normality, ppm, percentage and the like.</span>
The answer is “ COVALENT BOND”