mean of $200$ units and a standard deviation of $50$ units. At the beginning of each month, Galaxy orders enough goggles from its supplier to bring the inventory level up to $180$ goggles. If the monthly demand is less than $180,$ Galaxy pays $$20$ per pair of goggles that remains in inventory at the end of the month. If the monthly demand exceeds $180,$ Galaxy sells only the $180$ pairs of goggles in stock. Galaxy assigns a shortage cost of $$40$ for each unit of demand that is unsatisfied to represent a loss$-$of$-$goodwill among its customers. Management would like to use a simulation model to analyze this situation.