it's a qn from materials management. please help me to solve this

Halifax Cigar stocks Cuban cigars that have variable lead times because of the difficulty in importing the product Lead time is normally distributed with an average of 7 weeks and a standard deviation of 3 weeks. Demand is also a variable and normally distributed with a mean of 200 cigars per week and a standard deviation of 24 cigars. Refer to the standard normal table for z-values. This exercise contains only parts a and b. a) For a 90% service level, what is the ROP? The reorder point is cigars (round your response to the nearest whole number) b) What is the ROP for a 95% service level? The reorder point is cigars (round your response to the nearest whole number)