Joyce Murphy runs a courier service in downtown Seattle. She charges clients $0.47 per mile driven. Joyce has determined that if she drives 2,900 miles in a month, her total operating cost is $856. If she drives 4,700 miles in a month, her total operating cost is $1,108. Joyce has used the high-low method to determine that her monthly cost equation is total monthly cost $450 $0.14 per mile driven. Required: 1. Determine how many miles Joyce needs to drive to break even. 2. Calculate Joyce's degree of operating leverage if she drives 4,900 miles. 3. Suppose Joyce took a week off and her sales for the month decreased by 25 percent. Using the degree of operating leverage. calculate the effect this will have on her profit for that month