Between 1954 and 2003, swimmers have crossed Lake Ontario 43 times. Both women and men have made the crossing. Here are some plots (we've omitted a crossing by Vikki Keith, who swam a round trip North to South to North in 3390 minutes):
Summary statistics are as follows:
How much difference is there between the mean amount of time (in minutes) it would take female and male swimmers to swim the lake?
a) Construct and interpret a 95% confidence interval for the difference between female and male crossing times.
b) Comment on the assumptions and conditions.