BPH's inventory manager must set up ordering systems for the two following items: H1756 and J2973 based on the following data (assume that the weekly usage rates for both items are normally distributed). H1756 can be ordered at any time, but J 2973 can only be ordered every 3 weeks. Both items are used 52 weeks per year. a. When should each item be reordered? b. What is the EOQ for H1756? c. What is the order quantity for J2973 if the amount on hand when the order is placed is 20 units