Budgeted sales of the East End Burger Joint for the first quarter of the year are as follows:January $50,000February 60,000March 68,000 The cost of sales averages 40 percent of sales revenue and management desires ending inventories equal to 25 percent of the following month’s sales. Assuming the January 1 inventory is $5,000, the January purchases budget is: a. $19,000 b. $21,000 c. $31,000 d. $69,000