Answer:
31.9secs
6,183.3m
Explanation:
Given the equation that models the height expressed as;
h(t ) = -4.9t²+313t+269
At the the max g=height, the velocity is zero
dh/dt = 0
dh/dt = -9,8t+313
0 = -9.8t + 313
9.8t = 313
t = 313/9.8
t = 31.94secs
Hence it takes the rocket 31.9secs to reach the max height
Get the max height
Recall that h(t ) = -4.9t²+313t+269
h(31.9) = -4.9(31.9)²+313(31.9)+269
h(31.9) = -4,070.44+9,984.7+269
h(31.9) = 6,183.3m
Hence the maximum height reached is 6,183.3m