hmm 
Laash meray saamnay gir rahi hay 15ft say to meray uuper kitnay feet giray gi?
and your farmula is wrong, I cant make any sense out of it 
The body falls from 15ft to the ground.
the body is 6ft tall from the ground.
the Gravety is 9.8m/s
Mass = 66kg
K.E = 1/2 kesay ho sakta hay?
and its D=M/V budhu
You are giving different co-ordinates with differnt farmula..