Jawabanmu

2014-04-21T19:55:30+07:00
Jari2 = 12cm
garis tengah = 2phi
maka, 2.12 = 24 cm
2014-04-21T19:55:56+07:00
Dik : r = 12 cm
dit : d = ... cm
jwb : d = 2 x r
           = 2 x 12 cm = 24 cm