tolong bantu jawab ya ka

jawb

1. OA + 12 cm
sudut pusat   105
panjang busur = 105/360 x 2 x22/7 x 12
p = 7/24 x 22/7 x 24
p = 22 cm

2.
r= 10,5
panjang busur = 38,5
a/360 x 2 x 22/7 x 10,5 = 38,5 
a/360 x 66 = 38,5
a/360 = 38,5 / 66 = 7/12
a = 7/12 x 360
a= 210