Assume that aerodynamic resistance is ignored in the analysis.
The launch velocity is 40.8 m/s at an initial angle of 28°.
Therefore:
Vertical component of launch velocity is
v = (40.8 m/s)*sin(28) = 19.154 m/s
Horizontal component of launch velocity is
u = (40.8 m/s)*cos(28) = 36.024 m/s
At maximum height, the vertical component of velocity is zero, but the horizontal component remains the same because aerodynamic resistance is ignored.
Given: m = 0.15 kg, mass of baseball
The kinetic energy at maximum height is
KE = (1/2)*m*u²
= (1/2)*(0.15 kg)*(36.024 m/s)^2
= 97 .33 J
Answer: 97.3 J (nearest tenth)