What error did Heather make? Heather solved this problem:
75 is 300% of what number?
O None. Her work is correct?
O She multiplied 75 and 4 incorrectly.
O She should have divided 75 by 4, and divided 100
by 4.
O She used the part, 75, to write the percent ratio. The
part-to-whole percent ratio is 300/100

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.