A.90~115dB(A) B.70~85 dB(A) C.115 dB(A)以上 D.不得大于90 dB(A)
A.1~2km/h B.8~10 km/h C.3~5 km/h D.不少于10 km/h
A.90dB(A) B.95dB(A) C.80dB(A) D.85dB(A)