Abigail"s parents pay her $5 an hour for weeding the yard and pay her little sister $3 an hour for raking leaves. write and expression two different ways to represent the amount for parents will pay abigail and her sister from work you same amount of hours

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.