Water used in the US can be measured in acre-feet. (An acre is a unit of square area, equal to 4840yd2, and recall that there are three feet in a yard.) A typical family uses 0.62 acre-ft of water every ten months. Due to the drought in California, five families on one block decide to use purely desalinated water, which costs $2125 per acre-foot. How much does this block of families spend on their water over a four-year period?