Suppose that in the 4 days following a farmer's sale of September wheat futures at a futures price of $4.19 per bushel, the futures prices are as follows. Day 1 2 3 4 Price $4.21 $4.28 $4.36 $4.35 At the end of day 4 the farmer decides to close his entire position. The contract size is 14,000 bushels. If the initial margin of each contract is $30,000, what is margin balance at the end of day 4