Jawabanmu

2014-04-10T16:33:29+07:00
A. 1

Q= M.C.delta t
21000= 5.4200 .t
t= 21000/21000= 1
2014-04-10T17:19:57+07:00
Q= m.c.delta t 21.000=5.4200.t 21000=21000.t t=21000/21000= 1 (c)