For people who buy ice cream, the all-time favorite is still vanilla. About 25% of ice cream sales are vanilla. Suppose that 175 customers go to a grocery store in Cheyenne, Wyoming, today to buy ice cream. Using normal approximation for this binomial distribution Poin a) Which assumptions need to be satisfied in order for you to use the normal approximation for the binomial distribution? Verify. b) What is the probability that more than or equal to 55 people will buy vanilla without correction for continuity? c) What is the probability that less than or equal to 40 people will buy vanilla with correction for continuity?