Jawabanmu

2014-08-30T14:45:05+07:00
1/6*10N/kg=10/6
10/6*20=5
Jadi massa batunya 5N
2014-08-30T15:45:22+07:00
W = m.g
    =   20 N . 1/6 x 10
    = 200.1/6
    = 33, 3 N