An income statement for Crandall's Bookstore for the first quarter of the current year is presented below: CRANDALL'S BOOKSTORE Income Statement for the First Quarter of the Current Year Sales $800,000 560.000 240,000 Less: Cost of Goods Sold - all variable Gross Margin Less: Operating Expenses: Selling Administrative $98,000 98,000 196.000 Operating Income $44.000 On average, a book sells for $50. Variable selling expenses are $5.50 per book, with the remaining selling expenses being fixed. The variable administrative expenses are 3% of sales, with the remainder being fixed. a Required: a) Construct a contribution income statement to determine the operating income for the first quarter. b) What is the cost formula for operating expenses where X represents the number of books sold