Jawabanmu

2013-12-05T22:40:08+07:00
Vt = vo + at
vt = 20 + 5.3
vt = 20 + 15
vt =14 m/s

ek1/ek2 = (1/2mv02 ) / (1/2mvt2)
             = (1/2.400) / (1/2 . 196)
             = 200/98
             = 100/49