Kerjain yak no 58 Please

144°/360° × 2πr= 8,8
4/10 × 2πr= 8,8
2πr= 8,8 × 10/4
2×22/7 ×r = 22
44/7 r= 22
r= 22×7/44
r= 3,5 cm

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