Connolly Company produces two types of lamps, classic and fancy, with unit contribution margins of $13 and $21, respectively. Each lamp must spend time on a special machine. The firm owns four machines that together provide 18,000 hours of machine time per year. The classic lamp requires 0 20 hours of machine time, the fancy lamp requires 0.50 hours of machine time. What is the contribution margin per hour of machine time for a classic lamp? O. 565 Ob. 516 Oc. 513 Od. 526 O. 5104