Spring Company sells software during the recruiting seasons. During the current year, 11 000 software packages were sold resulting in 440 000 of sales revenue, 120 000 of variable costs, and 52 000 of fixed costs. If sales increase by 100 000, operating income will increase by: (Round interim calculations to two decimal places and the final answer to the nearest whole dollar.) a. 52 000 O b. 72 725 c. 48 000 O d. 37 504