Erica is making necklaces and bracelets to se at the craft show. it takes her 3 hours to make a necklace and 2 hours to make a bracelet. she sells the necklaces for $18 and the bracelets for $15. she has 60 hours available this coming week to make the jewelry, and would like to make at least 25 total pieces of jewelry, with at least 2 being necklaces. how many of each should she make to maximize her profit?

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?