Tolong dibantu ya besok dikumpulin

<MON/360° = panjang busur MN/keliling lingkaran
72°/360° = 31, 4 / keliling lingkaran
1/5 = 31, 4/keliling lingkaran
Keliling lingkaran = 157 cm

Keliling lingkaran = 2 π r
157 cm = 2 × 3, 14 × r
r = 25 cm

Luas lingkaran = πr²
= 3, 14 × 25²
= 1.962, 5 cm²
<MON/360° = luas juring OMN/luas lingkaran
72°/360° = luas juring OMN/1. 962, 5 cm²
1/5 = luas juring OMN/1.962, 5
Luas juring = 392, 5 cm²