K Data on 4700 college graduates show that the mean time required to graduate with a bachelor's degree is 4 53 years with a standard deviation of 1.35 years. Use a single value to estimate the mean time required to graduate for all college graduates. Also, find the 95% confidence interval for the mean time required to graduate for all college graduates. The estimate for the mean time required to graduate for all college graduates is 4 53 years (Round to two decimal places as needed.) Find the 95% confidence interval for the mean time required to graduate for all college graduates years