BE21-5 Pine Street Inc. makes unfinished bookcases that it sells for $62. Production costs De are $36 variable and $10 fixed. Because it has unused capacity, Pine Street is considering sel finishing the bookcases and selling them for $70. Variable finishing costs are expected to L be $6 per unit with no increase in fixed costs. Prepare an analysis on a per unit basis show ing whether Pine Street should sell unfinished or finished bookcases