2. The amount of juice dispensed from a machine is normally distributed with a mean of 10.5 oz and a standard deviation of 0.75 oz. a. about 68% of the amounts dispensed fall within what range?

b. About what percent of the time will the machine overfill the 12 oz cups?

c. a beverage that contained 9 oz of juice falls in what percentile?​

Afactory makes propeller drive shafts for ships. a quality assurance engineer at the factory needs to estimate the true mean length of the shafts. she randomly selects four drive shafts made at the factory, measures their lengths, and finds their sample mean to be 1000 mm. the lengths are known to follow a normal distribution whose standard deviation is 2 mm. calculate a 95% confidence interval for the true mean length of the shafts. input your answers for the margin of error, lower bound, and upper bound.