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Tom has 599 dollars to spend on two goods, good 1 and good 2. The seller of good 1 offers Tom the following deal: For every three units (of good 1) you buy, you will get the fourth unit for free. Determine how many units of good 7 Tom will end up with if the price of good 1 is 4, the price of good 2 is 4, Tom spends all his income on the two goods and buys 20 units of good 2. Then enter the value below