Compact Appliances Uses a Standard Part in the Manufacture of Several

Compact Appliances uses a standard part in the manufacture of several of its air conditioners.The cost of producing 40,000 parts is $110,000,which includes fixed costs of $50,000 and variable costs of $60,000.The company can buy the part from an outside supplier for $4.00 per unit,and avoid 40% of the fixed costs. If Compact Appliances makes the part,how much will its operating income be?

A) $30,000 greater than if the company bought the part
B) $80,000 greater than if the company bought the part
C) $20,000 greater than if the company bought the part
D) $120,000 greater than if the company bought the part