Sabor Inc. is a medical testing laboratory that performs several tests and analyses for hospitals in the area. Four of the tests that they perform require the use of a specialized machine that can supply 14,000 hours per year. Information on the four lab tests follows: Test A Test B Test C Test D Charging rate $65 $51 $48 S32 Variable cost $25 $18 $13 Machine hours What is the contribution margin per hour of machine time for Test A? $65 O $13.33 O $25.50 $40 O $15.67