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Marks The graph below represents the market of beef in Alpha, a small closed economy. The graph also shows the World price of beef. which is $10 a unit. 520 SIS $|0 20 30 40 45 50 Q Now, assume that Alpha opens up to trade with the rest of the world but imposes a tariff of $5 a unit on imports of beef Then, Alpha imports units of beef. Relative to autarky the consumer surplus changes by Alpha's aggregate welfare changes by dollars relative to autarky