Need some help please!

Sohar Computers assembles laptop computers from generic components. It purchases its colour monitors from a manufacturer in China with a lead time of one week. Daily demand for monitors is normally distributed with a mean of 40 monitors and a standard deviation of 8 monitors. The company has determined that the ordering cost is OMR 325 per order, the annual holding cost is OMR 25 per monitor, and the stockout cost is OMR 450 per lost sale. Currently Sohar Computers accepts a 5% risk of stockout. Assume 350 days per year and 7 days in a week a) What is the optimal order quantity? (2 marks) Optimal order quantity = monitors b) Sohar Computers applies a continuous review system. What is their reorder point? monitors Re-order Point - (3 marks) c) What is the cost of the safety stock? (1 mark) Cost - OMR d) With the current 95% service level, how many stockouts can be expected each year? stockouts (2 marks) e) Calculate the current fill rate. (3 marks) Fill rate - % f) If Sohar Computers is willing to spend 50% more on safety stock, what service level could be achieved? (2 marks) Service level % What is the annual cost of lost sales? (1 mark) cost of lost sales =