一昼夜秒针的针尖走过
= 20π×60×24
= 90432 cm
= 904.3 m
一昼夜分针的针尖走过
= 16π×24
= 1206.4 cm
= 12.06 m时针的针尖走过多少cm？一昼夜时针的针尖走过= 12π×2= 75.36 cm