Fifteen people were asked how many days it had been since they had eaten more than 50 grams of carbohydrates in a single day. The
results are shown above. What is the interquartile range of the data?
A,1 B,2 C,3 D,4
help me now

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.