Zionade Company manufactures a certain type of alloy. The alloy 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 alloy are as follows: Unit selling price $97.50 Unit variable cost (22.50) Unit contribution margin $75.00 Hardening treatment hours per unit 3 hrs. Assuming Zionade produces 2,000 units of the alloy, calculate the unit contribution margin per production constraint hour. 

a. $75 per hour 

b. $33 per hour 

c. $25 per hour 

d. $98 per hour