(Solved): average velocity please explain  A ball is thrown straight up with an initial velocity of \( 40 ...

A ball is thrown straight up with an initial velocity of \( 40 \mathrm{ft} / \mathrm{s} \). The height of the ball \( t \) seconds after launch is \( h(t)=40 t-16 t^{2}+5 \). (a) Find the average velocity of the ball over time intervals that begin 2 seconds after launch (i.e., at \( t=2 \) ) and last for the given lengths of time. i. \( .005 \) seconds ii. \( .002 \) seconds iii. \( .001 \) seconds (b) Estimate the instantaneous velocity of the ball at \( t=2 \).