In a report prepared by Economic Research Department of major bank, the department manager describes that the average annual family income on Metropolis is $48,432 and standard deviation is $1500. In order to test the claim, a manager in the different department in the bank randomly chooses 50 families from Metropolis. The manager then describes that since there're more than 30 observations in the random sample, the random sample of family income values follows (approximately) a Normal distribution. Do you agree with the manager? Please explain.