The heights of a random sample of 50 college students showed a mean of 174.5 centimeters and a standard deviation of 6.9 centimeters. (a) Construct a 95% condence interval (C.I.) for the mean height of all college students. (b) What can we assert with 95% condence about the possible size of our error if we estimate the mean height of all college students to be 174.5 centimeters? (c) Construct a 99% CI. for the mean height of all college students. Compare with the 95% CI. obtained in (a) and comment