The formula for Kinetic Energy is KE= k(mv^2)/2,
where k is the proportionality constant,
m is the mass in kg,
v is the velocity in m/s.
By using the first set of data, we get:
4500=k (90 x 20^2)/2
which gives k a value of 0.25.
For the second set of data, we use the same formula:
KE = k(mv^2)/2
KE = 0.25 (90x32^2)/2
Finally, we get the value KE = 11, 520 J.
*note that J = (kg m^2)/s^2