PB17. LO 10.6 Sports Buffs makes basketballs and footballs in a three-step process. Unfortunately, the stem insertion process has been identified as a bottleneck. Each basketball has a contribution margin of $15.00 and each football has a contribution margin of $4.00. The stem insertion equipment can make 10 basketballs or 30 footballs in one hour. A. If demand for both products is unlimited and the stem insertion machine capacity cannot be expanded, which product should be produced? B. If demand for each ball is limited to 9,000 balls and there are 4,000 hours available on the machine, how many of each product should be produced