Elizabeth Ann Kreh is a designer of a custom clothing line and accessories and founder of EAK Company. The following contribution format income statement is based on a sales volume of 2,500 custom backpacks, and the relevant range of production is 500 units to 5,000 units): Sales Revenue $375,000 Variable Expenses ( 168,750) Contribution Margin 206,250 Fixed Expenses ( 75,000) Net Operating Income $131,250 56. If sales increased to 3,650 units what will be the contribution margin? (Additionally, prepare a worksheet proof.) 57. If sales increased to 3,650 units what will be the net operating income? (Additionally, prepare a worksheet proof.) 58. If sales declined to 1,750 units what will be the contribution margin ratio? (Additionally, prepare a worksheet proof.) 59. If sales declined to 1,750 units what will be the net operating income? (Additionally, prepare a worksheet proof.)