Aircraft Products, a manufacturer of aircraft landing gear, makes 1,100 units each year of a special valve used in assembling one of its products. The unit cost of producing this valve includes variable costs of $71 and fixed costs of $65. The valves could be purchased from an outside supplier at $78 each. If the valve were purchased from the outside supplier, 40% of the total fixed costs incurred in producing this valve could be eliminated. Buying the valves from the outside supplier instead of making them would cause the company's operating income to:

Increase by $35,200.

Increase by $20,900.

Decrease by $20,900.

Decrease by $35,200.