Dylan is going to a college where tuition is $7000 per year. he has a scholarship that pays 80% of tuition. his uncle is giving him 1000 per year. how much will dylan need to borrow to pay tuition each year?

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.