3. The Newtower Department Store has experienced a 3.2% rate of customer complaints and attempts to lower this rate with an employee retraining program. Aer the retraining program, 850 customers are observed. Let x = the number of complaints out of the 850. (a) Why is this a binomial experiment? (b) Is the probability histogram approximately bell shaped? (0) Assuming that the retraining had no effect, nd the mean and standard deviation for the number of complaints that would arise from a group of 850 customers