tolong jawab dengan caranya

1.
r = 14 cm , busur AB = 22 cm

a. d = 2r = 2 x 14 = 28 cm
b. keliling = 22/7 x 28 = 616/7 = 88 cm
c. sudut AOB = 22/88 x 360° = 90°

2.
r = 10 cm
d = 20 cm
keliling = 3,14 x 20 = 62,8
a. 30° = 62,8/12 = 5,23 cm
b. 60° = 62,8/6 = 10,47 cm
c. 90° = 62,8/4 = 15,7 cm
d. 120° = 62,8/3 = 20,94 cm
e. 180° = 62,8/2 = 31,4 cm