Jawabanmu

2014-09-08T19:36:48+07:00
v = 22/7 * r * r * t
154 = 22/7 * r^2 * 12
154 * 7/22 = 12 r^2
49 = 12r^2
49/12 = r^2
r = 7 (akar) 12
2014-09-08T19:38:34+07:00
√21.v per 22 t = √21.154 per 22.12 = √3234 per 264 = √12,25 = 3,5
mudah"an betul :D