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Calculate: 1- The cost of payables if your supplier's terms are 4/15 net 60 2- The Optimal Order Size if the firm sells 1,750,000 units per year, carrying cost per inventory unit is $60 and the cost of making each order is $745. How many orders does this firm make each year? 3. Suppose money markets yield 1% and the cost of making a transaction is $50. If a firm has an annual cash requirement of $1,000,000 (using Baumol) predict the size and frequency of its movements between cash and securities