Jawabanmu

2014-09-07T10:08:26+07:00
24. 1/2.m.v^2
     =1/2.0,02 kg.400^2 m/s
     =1600 joule
26.1/2.m.v^2
     =1/2.15 kg.4^2 m/s
     =120 joule
27. 1/2.m.v^2
     =1/2.45kg.4^2 m/s
     =360 joule