The Science Club went on a two-day field trip. The first day the members paid $40 for transportation plus $11 per ticket to the planetarium. The second day they paid $90 for transportation plus $8 per ticket to the geology museum. Write an expression to represent the total cost in dollars for two days for the n members of the club.

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?