A ball is thrown into the air by a baby alien on a planet in the system of Alpha Centauri with a velocity of $40f\frac{t}{s}.$ Its height in feet after $t$ seconds is given by $y=40t-17t^2.$

A$.$ Find the average velocity for the time period beginning when $t=3$ and lasting

$\mathrm{.}01s$:

$\mathrm{.}005s$:

$\mathrm{.}002s$:

$\mathrm{.}001s$:

NOTE: For the above answers, you may have to enter $6$ or $7$ significant digits if you are using a calculator.

Estimate the instanteneous velocity when $t=3.$