Wall mart Manufacturing produces a product that sells for $75. Fixed costs are $350.000 and variable costs are $20 per unt. Winthrop can buy a new production machina mat will increase bad costs by $13,200 per year, but will decrease variable costs by $2 per unit. Compute the contribution margin per unit if the machine is purchased O a $40.00 Ob. $51.00 O c $45.00 Od $52.00 e. $49.00