tolong dibantu susah ni please no 13

K = Phi x d
= 3,14 x 20
= 62,8 cm

Semoga Membantu :)

Diameter = 2r
20 cm =2r
r = 10 cm
Keliling lingkaran = 2 x phi x r
= 2 22/7 10
= 62,8 cm (C)