You are the manager of ABC restaurant. You notice that the consumer's waiting time in your restaurantis normally distributed with a mean time of 10 minutes. Use the empirical rule to answer the following questions:

a. If 99.7% of the consumers wait between 4 and 16 minutes, what is the standard deviation?

b. Given (a), what percentage of consumers wait between 8 and 12 minutes?

c. If the service of your restaurant is improved and now 95% of the consumers wait between

5 and 11 minutes, what are the new mean and new standard deviation?