A ball is thrown upward from the ground with an initial velocity of . If the positive direction of the distance from the starting point is the equation of the motion according to the formula , find the instantaneous velocity of the ball at the end of seconds?
. Isaac was holding a stopwatch and recorded that the time it took for the ball to reach the ground was 
. Isaac bet that the ball had reached its maximum height before 
second. Angelica bet that it's not possible and bet that it reached its maximum height after 
where acceleration due to gravity is 
and 
is the initial velocity and height from the ground, respectively.
,its height (in feet) after 
seconds is given by
.find the velocity when 
.
