Milden Company is a distributor who wants to start using a contribution format income statement for planning purposes. The company has analyzed its expenses and developed the following cost formulas: Because shipping expense is a mixed cost, the company needs to estimate the variable shipping expense per unit sold and the fixed shipping expense per quarter using the following data: Required: 1. Using the high-low method, estimate a cost formula for shipping expense in the form Y=a+bX. 2. In the first quarter of Year 3 , the company plans to sell 23,000 units at a selling price of $51 per unit. Prepare a contribution format income statement for the quarter