Suppose That a New Alloy Is Invented Which Uses Copper

suppose that a new alloy is invented which uses copper and zinc in fixed proportions where 1 unit of output requires 3 units of copper and 3 units of zinc for each unit of alloy produced.If no other inputs are needed, the price of copper is $4, and the price of zinc is $5, what is the average cost per unit when 4,000 units of the alloy are produced?

A) $1.33
B) $14.17
C) $1,333.33
D) $27
E) $14,166.67