When Tallulah runs the 400 meter dash, her finishing times are normally distributed with a mean of 79 seconds and a standard deviation of 0.5 seconds. Using the empirical rule, what percentage of races will her finishing time be between 78 and 80 seconds?

The physical fitness of an athlete is often measured by how much oxygen the athlete takes in (which is recorded in milliliters per kilogram, ml/kg). the mean maximum oxygen uptake for elite athletes has been found to be 60 with a standard deviation of 7.2. assume that the distribution is approximately normal.

Abby is preparing fruit punch for her party. she starts with a bowl filled with liquid that has 1/2 fruit juice and 1/2 sprite, but she decides it's too fruity. so she pours out 1/4 of the liquid, and then fills the bowl up again with sprite. what fraction of the punch is now sprite?

Acylinder has volume 45π and radius 3. what is it’s height?