28. (TCO 4) The following monthly data are available for RedEx, which produces only one product that it sells for $84 each. Its unit variable costs are $28, and its total fixed expenses are $64,960. Sales during April totaled 1,600 units. (a) How much is the break-even point in sales dollars for RedEx? (b) How many units must RedEx sell in order to earn a profit of $24,640? (c) A new employee suggests that RedEx sponsor a company softball team as a form of advertising. The cost to sponsor the team is $1,792. How many more units must be sold to cover this cost? (Points : 25)