need help with this one

Innovative Electronics currently manufactures most of the component parts used in its three major products. Two of the products use part number 101 and the company has been presented an option to buy part number 101 from a new supplier at $68 per unit. Current production costs per unit for part number 101 include direct materials, $30; direct labor, $15; variable overhead, $10; and fixed overhead, $20. If Innovative buys part number 101 from the new supplier, several salaried positions could be eliminated which would reduce the fixed overhead amount by 25%. Comparing the relevant cost to make versus buy part number 101 determines that there is: Multiple Choice a $2 per unit advantage to buy. a $7 per unit advantage to buy. an $8 per unit advantage to make. a \$15 per unit advantage to make