Amachine produces metal rods used in an automobile suspension system. a random sample of 15 rods is selected, and the diameter is measured. the resulting data (in millimeters) are as follows: 8.24 8.25 8.20 8.23 8.24 8.21 8.26 8.26 a.20 8.25 8.23 8.23 8.19 8.28 8.24 (a) calculate a 99% two-sided confidence interval on mean rod diameter.

Assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.