Answer:
240 m to nearest meter.
Step-by-step explanation:
h = -4.9t^2 + 68.6t
We need to convert this to vertex form to find the maximum value of h:
h = -4.9(t^2 - 14t)
h = -4.9[(t - 7)^2 - 49]
h = -4.9(t - 7)^2 + 240.1
So maximum height is when t = 7 and it's 240.1 meters.