Dan and Glenn are swimming buddies who love to challenge themselves while diving T hold his breath underwater, D. is 111 seconds with a standard deviation of 125 seconds can hold his breath underwater, G. is 105 seconds with a standard deviation of 10 9 sec are independent random variables and X=D-G What is the probability that on any given dive Dan holds his breath for less time than Glen? 0 .108 0.359 0.397 0.641 ​

The management of a supermarket wants to adopt a new promotional policy of giving a free gift to every customer who spends more than a certain amount per visit at this supermarket. the expectation of the management is that after this promotional policy is advertised, the expenditures for all customers at this supermarket will be normally distributed with a mean of $95 and a standard deviation of $20. if the management wants to give free gifts to at most 10% of the customers, what should the amount be above which a customer would receive a free gift?