math
posted by katy on .
The National Center for Education surveyed 4400 college graduates about the lengths of time required to earn their bachelor's degrees. THe sample mean is 5.15 years, and assume that the population standard deviation is known to be 1.68 years. Based on gthe sample data, construct the 99% confidence interval for the mean time required by all college graduates.
Also, determine the margin of error, E.

Both the balls will meet at 8.9m above the ground.