The University Stom. Incorporated is the major bookseller for four nearby colleges. An Income statement for the first quarter of the year is presented below: University Store. Incorporated Income Statement For the Quarter Ended March 31 Sales Cost of goods sold Gross margin Selling and administrative expenses Selling Administrative Net operating Income $100,000 $800.000 560.000 240,000 110.000 210,000 $30,000 On average, a book sells for $40.00. Variable selling expenses are $3.00 per book the remaining selling expenses are fixed. The variabi ministrative expenses are 5% of sales; the remainder of the administrative expenses are fixed. The net operating income computed using the contribution approach for the first quarter is $140,000 O $30,000 O $180.000 050