Magenta Company manufactures a certain type of metal. The metal undergoes a hardening process. The hardening unit is operating at full capacity and is a production constraint. The unit contribution margin and the number of hours of hardening treatment used by the metal are as follows: Unit selling price $95.85 Unit variable cost (21.90) Unit contribution margin $73.95 Hardening treatment hours per unit 5 hrs. Assuming Magenta produces 2,500 units of the metal, calculate the unit contribution margin per production constraint hour. Round your final answer to nearest whole dollar. a. $22 per hour b. $15 per hour c. $74 per hour d. $37 per hour