Kevin is buying water for his camping trip. He knows he needs at least 20 gallons of water for the trip. He already has five and a half gallons. The water comes in 32-fluid ounce (quarter-gallon) containers.

Let x be the number of
containers of water.
The expression that represents the total amount of water is
.
If the total amount of water must be at least 20 gallons, then it must be
20.