Calculate the 2 horizontal and verticle vectors of the velocity 78 m/s
the horizontal vector is what we want becoz the verticle vector is goin to be 0 at the max height.
the horizontal vector if 7.8Cos(17) = 7.46 m/s
So, now we have the velocity and we already have the mass, we can calculate KE,
.5(m)(v)^2
= 5779.8 J
I hope my answer is right, if not just comment, i will help u
:)