A.脈沖信號B.電平信號C.電量信號D.載波信號
A.70%~90%B.75%~90%C.70%~80%D.70%~85%
A.手動召測B.自動召測C.隨機(jī)召測數(shù)據(jù)D.指定召測數(shù)據(jù)