9. In the fixed order quantity model, if the standard deviation of the daily demand (d) increases (while other system parameters are kept the same), then a. The optimal order quantity increases b. The average number of orders placed every year increases c. The annual holding cost increases d. The safety stock decreases 10. Consider a newsvendor model with normally distributed demand. Suppose that the cost of overage is greater than the cost of underage. If the demand variance is reduced, a. The optimal order quantity increases. b. The optimal order quantity stays the same. c. The optimal order quantity decreases. d. Cannot say. If needed, you can assume the following with regards to the normal distribution service level values: - for a 95\% service level, z=1.65 - for a 92.65% service level, z=1.45 - for a 87.5% service level, z=1.15 - for a 82.12% service level, z=0.92 - for a 79.10% service level, z=0.81 - for a 73.47% service level, z=0.63 - for a 69.15% service level, z=0.50 - for a 62.55% service level, z=0.32 - for a 55.11% service level, z=0.13 - for a 52.39% service level, z=0.06