In 1 second the watermelon would be 10.7m above the ground. 2 seconds, 21.4m, 3 seconds,32.1m so on, so forth.
PE = mgh
so (75kg)(9.8m/s2)(100m) = 73,500 Joules
KE = 1/2 m * v^2
so (1/2)(75kg)(60m/s)^2 = 135,000 Joules
ME = 208,500 Joules
The advantage is that we do not run out of resources and a disadvantage is that is dangerous when a “human” gets too close and gets sick by the radiation.
I think it’s A.at the origin