a ball is thrown into the air with a velocity of 40 ft/s, its height in feet seconds later is given by y=40t-16t^2. a) Find the
average velocity for the time period beginning when and lasting (i) 0.5 second (ii) 0.1 second (iii) 0.05 second (iv) 0.01 second (b) Estimate the instantaneous velocity when t=2
