Answer:
Below in bold.
Step-by-step explanation:
Starting height is when t = 0
It is 5 units.
To find the maximum height we convert the equation to vertex form:
h = -t^2 + 4t + 5
h = -(t^2 - 4t - 5)
= - [(t - 2)^2 - 9]
= -(t - 2)^2 + 9
From this we see that the ball reaches max height after 2.
Maximum height = -2^2 + 4(2) + 5
= 9 units.
Ball reaches the ground after 2*2 = 4 .
