Aball is thrown into the air by a baby alien on a planet in the system of alpha centauri with a velocity of 27 ft/s. its height in feet after t seconds is given by y = 27 t − 20 t 2 y=27t-20t2. a. find the average velocity for the time period beginning when t=3 and lasting .01 s: preview .005 s: preview .002 s: preview .001 s: preview 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. preview get : video