If a ball is thrown into the air with a velocity of 40ft./s its height in feet t seconds later is given by y=40t-16t^2.
a.)Find the average velocity for the time period beginning when t=2 and lasting
i.) 0.5 seconds ii.)0.1 seconds
iii.)0.05 seconds iv.)0.01 seconds
b.) Estimate the instantaneous velocity when t=2.
I am totally stuck I am not sure where to start I know. I know have to plug in the various times into the equation they gave. I also know that this problem has something to do wit-av. velocity=change in distance / change in time.