The given equation is
where h is the height, in feet, of a ball and t is the time, in seconds.
<u>Part a: The height of the ball when t = 2 seconds:</u>
The height of the ball above the ground 2 seconds after it is released can be determined by substituting t= 2 in the equation
, we get;

Simplifying the terms, we get;


Thus, the height of the ball after 2 seconds is 100 feet.
<u>Part b: The height of the ball when t = 4 seconds:</u>
The height of the ball above the ground 4 seconds after it is released can be determined by substituting t = 4 in the equation
, we get;

Simplifying the terms, we get;


Thus, the height of the ball after 4 seconds is 68 feet.