Ahair salon charges a fixed rate of $25.00 for a haircut and then an additional $15 for any other services. write a function to model the cost of services there and then evaluate it if you also get a shampoo, highlight, and blow dry.

According to a study conducted in 2015, 18% of shoppers said that they prefer to buy generic instead of name-brand products. suppose that in a recent sample of 1500 shoppers, 315 stated that they prefer to buy generic instead of name-brand products. at a 5% significance level, can you conclude that the proportion of all shoppers who currently prefer to buy generic instead of name-brand products is higher than .18? use both the p-value and the critical-value approaches.