A market surveyor wishes to know how many energy drinks teenagers drink each week. They want to construct a 80%80% confidence interval with an error of no more than 0.070.07. A consultant has informed them that a previous study found the mean to be 3.63.6 energy drinks per week and found the variance to be 1.441.44. What is the minimum sample size required to create the specified confidence interval? Round your answer up to the next integer.

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?