Because of it being able to become a gas, a liquid, and solid, and because its used in lots of chemical experiments. (also because its easier to describe it than any other liquid)
Explanation:
1. Water is used in most Chemicals, therefore its being used as a reference material.
The price p to sell your skateboards for so that there is neither a shortage nor a surplus is the price that makes equal the quantity of sales and the quantity of supply, so p is equal to:
