Jawabanmu

2014-02-10T19:13:18+07:00
K = phi x 2r
K = 3,14 x 10.5 x 2
K= 65,94 cm

L = phi x r"
L = 3,14 x (10,5)"
L = 346,185 cm^2
2014-02-10T19:14:37+07:00
r = 10,5 cm
d = 21
k = 22/7 x 21
k = 66 cm
L = 1/4 x 22/7 x 21^2
L = 5,5 x 63
L = 346,5 cm^2