Assume that private preschool costs in the city are normally distributed. the average amount that NYC parents pay for private preschool is mean= 27,500 a year with standard deviation= 7,740 a. find the probability a preschool in NYC is less than 20,000 a year
b. find the probability that for three families the average amount a preschool in NYC will cost them will be more than 40,000 a year
c. find the probability that a preschool will be between 18,000 and 35,000 a year
d. find the probability that for 5 families the average amount a preschool in NYC will cost them will be less than 32,000 a year​