The dot plot below shows the number of cakes 31 chefs made in a week:

is the median or the mean a better center for this data and why?

mean; because the data is skewed and there are outliers
mean; because the data is symmetric and there are outliers
median; because the data is not skewed and there are outliers
median; because the data is not symmetric and there are outliers

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.