The Barrister Mug Company manufactures plastic mugs that sell to wholesalers for $4.60 each. Variable and fixed costs are as follows: Variable Costs per Unit Manufacturing: Direct materials Fixed Costs per Month $0.69 Factory overhead Direct labor 0.81 Selling and adm. Factory overhead 0.57 $2.07 Total Selling and adm. 0.46 Total $2.53 $ 9,200 6,900 $16,100 Barrister Mug produced and sold 11,500 cups during April 2018. There were no beginning or ending inventories. Required: a. Determine Barrister Mug's monthly break-even point in units. b. If monthly sales increase by 575 cups, what will be the change in monthly profits? C. If Barrister Mug is now subject to an income tax of 40 percent, what dollar sales volume is required to earn a monthly after-tax net income of $13,800?