The times for the mile run of a large group of male college students are approximately normal with mean 7.09 minutes and standard deviation 0.77 minutes. use the 68-95-99.7 rule to answer the following questions. (start by making a sketch of the density curve you can use to mark areas on.) (a) what range of times covers the middle 68% of this distribution? (b) what percent of these men run a mile in more than 9.4 minutes? (a) from 6.32 minutes to 7.86 minutes (b) 13 %