21. A farmer is filling a hole in his farm with dirt. He measures the hole to be in the shape
of a rectangular prism measuring 12 feet by 4
feet by 3 feet. If the cost of dirt is $1.25 per
cubic foot, then how much will he spend?

Real gross domestic product: a) will increase if the price level increases. b) can change from one year to the next even if there is no change in output. c) will increase if the level of output increases. d) is a measure of inflation.