kaka kakaaa tolongin donkk... pake cara yahhhh:)

diameter =21
jari2 = 21 : 2 = 10,5
.
= 2 × 3,14 × 10,5 × 1/2
= 32,97

jd total nya = 32,97 ×3 = 98,91

maaf kalau salah.. ;')