A.起算數(shù)據(jù)誤差 B.鋼尺長度誤差 C.水準(zhǔn)尺讀數(shù)估讀誤差 D.經(jīng)緯儀度盤偏心誤差
A.±8.7mm B.±10mm C.±20mm D.±28.2mm