Jawabanmu

2014-04-18T21:42:36+07:00
33 = 3,14 . 2 r
r = 21
Luas = 22/7 . 21 .21 = 1386 cm2
2014-04-18T21:46:21+07:00
33= phi d 33 = 22/7 d d = 33 * 7/22 d = 10.5 r = 5.25 Ll = phi r'2 = 86.625