A.10mmB.15mmC.20mmD.25mm
A.2s~3sB.3s~5sC.2s~4sD.1s~3s
A.小數(shù)點(diǎn)后一位B.小數(shù)點(diǎn)后二位C.小數(shù)點(diǎn)后三位D.整數(shù)