8×2×3.14×(3÷60)=2.512(厘米)
C = 3÷60×2πr= 1÷20×2×3.14×8= 2.512 (厘米姿答贺)答:针尖走过 2.512 厘米迹派举闷.
2×8=16cm16×3.14=50.24cm50.24×3=150.72cm