Sarah's parents are filling their swimming pool. she wants to know how long it will take. what unit is best used to give the rate of the water flowing into the pool? her pool is 22,000 gallons. what unit will the answer to her question be answered in? a) cups per hour; hours b) gallons per hour; hours c) cups per minute; minutes d) gallons per second; seconds

B) gallons per hour

Step-by-step explanation:

The pool volume is measured in gallons, so that is the appropriate unit for use in the rate. The time will likely be measured in hours (not minutes or seconds), so that, too, is the appropriate unit for the rate.

Comment on other units

If the pool is filled from a fire hose or other high-volume source of water (irrigation pump, for example), the appropriate units may be gallons per minute. (It might only take 10 to 20 minutes.)

In a metric country, the appropriate units might be liters per minute or hour, or cubic meters per minute or hour. (The pool volume is about 83.3 m³.)

For the problem here, the unit of cups is way too small to be of interest, and (large volume) flow rates are rarely expressed in cups per unit time.