Many college graduates who are employed full-time have longer than 40-hour work weeks. Suppose that we wish to estimate the mean number of hours, , worked per week by college graduates employed full-time.We'll choose a random sample of college graduates employed full-time anduse the mean of this sample to estimate Mean . Assuming that the standarddeviation of the number of hours worked by college graduates is 6.30 hoursper week, what is the minimum sample size needed in order for usto be 99% confident that our estimate is within 1.2hoursper week of Mean ?

Carry your intermediate computations to at least three decimal places. Write your answer as a whole number (and make sure that it is the minimum whole number that satisfies the requirements).