Jawabanmu

Jawaban paling cerdas!
2014-06-05T16:36:18+07:00
2014-06-05T16:37:26+07:00
Q = m x c x ΔT
    = 4 kg x 4200 J/kg°C x (60°C - 20°C)
    = 4 kg x 4200 J/kg°C x 40°C
    = 672000 joule
Semoga membantu :-)