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16. To complete an order for making curtains, Rosie will need to employ three seamstresses for two days at 30 per day. It will also take 5 hours of her time, which she costs out at 10 per hour. She will receive 500 and have to buy materials of 220. If she accepts this order, she will have to turn down another order, which would have generated a contribution of 80. How much contribution will she make? a) 100 b) 20 c) None d) 50