Healthier Cook Company Manufactures Two Products: Toaster Ovens and Bread

Healthier Cook Company manufactures two products: toaster ovens and bread machines. The following data are available: $$\begin{array} { | l | r | r | } \hline & \text { Toaster Ovens } & \text { Bread Machines } \\\hline \text { Sale price } & \$ 80 & \$ 150 \\\hline \text { Variable costs } & \$ 40 & \$ 70 \\\hline\end{array}$$ Healthier Cook can manufacture six toaster ovens per machine hour and four bread machines per machine hour. Healthier Cook's production capacity is 1,800 machine hours per month. What is the contribution margin per machine hour for bread machines?

A) $20
B) $240
C) $320
D) $7