When comparing volume using imperial units, there are 5 common units to compare: fluid ounces (fl oz), cups, pints (pt), quarts (qt), and gallons (gal).
1 gallon (gal) = 4 quarts (qt)
1 quart (qt) = 2 pints (pt)
1 pint (pt) = 2 cups
1 cup = 8 fluid ounces (fl oz)
If we have a volume in gallons and we want to know how many quarts it is, we multiply the number of gallons by 4.