For a Firm, Let Total Cost Be $T C ( Q ) = 10 Q ^ { 2 }$

Multiple Choice

For a firm, let total cost be $T C ( Q ) = 10 Q ^ { 2 }$ and marginal cost be $M C ( Q ) = 20 Q$ . Which of the following is an expression for the output elasticity of total cost?

A) $\epsilon _ { T C , Q } = 10 Q$ .
B) $\epsilon _ { I C , Q } = 2 Q$ .
C) $\epsilon _ { T C , Q } = 2$ .
D) $\epsilon _ { T C , Q } = 20 Q$ .