TB Problem Qu. 23-129 (Algo) Computing contribution margin per unit and per machine hour A company makes computers and phones. Computers use 10 machine hours per unit. Phones use 4 machine hours per unit. Per unit variable costs and selling prices follow. Computer Phone Sales price per unit $ 1, 800 $ 960 Variable costs per unit 806 B80 a) For each product, calculate contribution margin per unit. b) For each product, calculate the contribution margin per machine hour. Computer Phone (a) Contribution margin per unit (b) Contribution margin per machine hour