The injection molding department of a company uses an average of 30 gallons of special lubricant a day. the supply of the lubricant is replenished when the amount on hand is 170 gallons. it takes four days for an order to delivered.safety stock is 50 gallons,which provides a stock out risk of 9 percent. what amount of safety stock would provide a stockout of 3 percent? Assume normality.