Part D

Let's look at the graph of the two functions and also the graph of their difference.

Input := 


Plot[{v[t],v2[t]},{t,0,endTime}]

Output =


-Graphics-

Input := 


voldiff[t_]=v[t]-v2[t];

Input := 


Plot[voldiff[t],{t,0,endTime}]

Output =


-Graphics-

To determine when the two volume difference is greatest we3 set the difference volume function's derivative equal to 0.

This is the value of t that would represent the time the volumes differ the most. And they differ by 62.66 ml at time t = 1.57 min.