Kitchen Convenience Company manufactures two products-toaster ovens and bread machines. The following data are available: Sales price Variable costs Toaster Ovens Bread Machines $120 $20 $150 $60 Kitchen Convenience can manufacture six toaster ovens per machine hour and four bread machines per machine hour. Kitchen Convenience's production capacity is 1,600 machine hours per month. What is the contribution margin per machine hour for bread machines? A. $360 B. $100 C. $540 D. $90