The Percentage Contribution Margin (PCM) for Each Firm in a Cournot

Multiple Choice

The percentage contribution margin (PCM) for each firm in a Cournot equilibrium can be calculated using the following formula:

A) $\frac { P - M C } { P } = \frac { 1 } { N } \times \frac { 1 } { \varepsilon _ { Q f} }$
B) $\frac { P - M M C } { P } = \frac { 1 } { N } \varepsilon _ { Q , P }$

C) $\frac { P - M C } { P } = - \frac { 1 } { N } \times \frac { 1 } { \varepsilon _ { Q f} }$
D) $\frac { P - M C } { P } = - \frac { N } { N + 1 } \times \frac { 1 } { \varepsilon _ { Q f } }$