If a ball is thrown straight up into the air with an initial velocity of $50$ ft/s, its height in feet after $t$ seconds is given by $y = 50 t - 16 t^2$. Find the average velocity for the time period beginning when $t = 2$ and lasting

(i) $0.5$ seconds:

(ii) $0.1$ seconds:

(iii) $0.01$ seconds:

(iv) $0.0001$ seconds:

Finally, based on the above results, guess what the instantaneous velocity of the ball is when $t =2$.
Answer: