help me please !!

Authentic Thai rattan chairs are delivered to Gary Schwartz's chain of retail stores, called The Kathmandu Shop, once a year. The reorder point, without safety stock, is 200 chairs. Carrying cost is $20 per unit per year, and the cost of a stockout is $80 per chair per year. Given the following demand probabilities during the lead time, how much safety stock should be carried? Demand During Lead Time 0 100 200 300 400 Probability 0.2 0.2 0.2 0.2 0.2 units (enter your response as a whole The optimal quantity of safety stock which minimizes expected total cost is number). Authentic Thai rattan chairs are delivered to Gary Schwartz's chain of retail stores, called The Kathmandu Shop, once a year. The reorder point, without safety stock, is 200 chairs. Carrying cost is $20 per unit per year, and the cost of a stockout is $80 per chair per year. Given the following demand probabilities during the lead time, how much safety stock should be carried? Demand During Lead Time 0 100 200 300 400 Probability 0.2 0.2 0.2 0.2 0.2 units (enter your response as a whole The optimal quantity of safety stock which minimizes expected total cost is number)