<h2>
Explanation:</h2>
In this problem we have a pumpkin is launched from the top of a 20 foot tall platform at an initial velocity of 84 feet per second. So the height, h, of the pumpkin at time t seconds after the launch can be modeled by the equation:

So this is the equation of a parabola. The maximum of this parabola occurs at its vertex. So let's find this vertex:

Finally, the maximum occurs at time 2.625 seconds when the height is 130.25m
3x-4y=12
4y=3x-12
y=(3x-12)/4
y=(3/4)x-3
Multiply 137 by 3 to get an answer of 411
13 is 141. A octagon has 1080 degrees and if you add all the angles up you get 939 and 1080-930=141