According to an NRF survey conducted by BIGresearch, the average family spends about $237 on electronics (computers, cell phones, etc.) in back-to-college spending per student. Suppose back-to-college family spending on electronics is normally distributed with a standard deviation of $54. If a family of a returning college student is randomly selected, what is the probability that: (a) They spend less than $150 on back-to-college electronics?
(b) They spend more than $400 on back-to-college electronics?
(c) They spend between $115 and $175 on back-to-college electronics?