Here's some additional information about the Ontario crossing times presented in Exercise 79. It is generally thought to be harder to swim across the lake from north to south. Indeed, this has been done only 5 times. Every one of those crossings was by a woman. If we omit those 5 crossings, the box plots look like this:

Although not designated as an outlier, the slowest female time belongs to Vikki Keith, who crossed the lake swimming only butterfly stroke. Omitting that extraordinary swim gives the following summary statistics:

a) Do women or men appear to be faster at swimming across the lake? Support your answer by interpreting a confidence interval (Use 32 df).
b) Some might argue that the men are being unfairly slowed down by two extraordinarily slow swims. Here are the summaries without those two swims. Repeat a) based on these data. Does your conclusion change? (Use 42 df).

c) Vikki Keith was responsible for two of the more remarkable crossings, but she also swam Lake Ontario two other times. In fact, of the 50 crossings in this analysis, 7 were repeat crossings by a swimmer who'd crossed the lake before. How does this fact affect your thoughts about the confidence interval?