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Q8 A- A retailer sells the Ultra-Man toy robot, The demand for the product follows a normal distribution with an average of 15 units per day and a standard deviation of 8 units per day, The unit cost of the product is $ 60, the cost of order is $ 50 with a four (4) day lead time, and the annual warehousing cost is $ 10. The retailer operates for 350 days per year, The firm decides to adopt a periodic review inventory system (fixed interval model) with an interval of 12 days between two orders and a supply lead time of four (4) days . If the initial inventory is 50 units, what quantity must be ordered (QC) so that 86% of the demand can be met during the review period (Type I service)? B- A retailer sells the Ultra-Man toy robot. The demand for the product follows a normal law with an average of 15 units per day and a standard deviation of B units per day. The unit cost of the produc is 60$, the cost to order is 50 $ with a lead time of four (4) days, and the annual cost of warehousing is 10s. The retailer operates 350 days a year. It is assumed that the firm decides to adopt the continuous revision inventory system (fixed quantity model) and that it wishes to contain the risk of shortage to a maximum of 8% (Type I service). Calculate the economical quantity to order.T