The size of the US, in cubic miles, depends on how deep into the earth and how far up into space is considered to be part of the US.
3.21 (cubic miles) = 3.53458604 × 1012 US gallons
176,637,542,400 cubic feet.
The Imperial gallon, which is used in Canada, is about 277.42 cubic inches. In contrast. the US gallon is 231 cubic inches.351 miles/21 US gallons * 1 US gallon/231 cubic inches * 277.42 cubic inches/Canadian gallon = 20.07 miles per Canadian Gallon
About 478,567,990.765 cubic miles
1,180.62 cubic miles.
399 cubic miles = 5.87319828 × 1013 cubic feet
23 cubic miles = 9.5868182 × 1010 cubic meters.
1.29931823 × 10^15 US gallons
1 cubic kilometer=1,000,000,000 cubic meters
330 cubic miles
3375000000 cubic miles 3.375 billion cubic miles
5,000 US gallons equates to about 668.4(668.402778) cubic feet.