A.視準軸CC∥水準管軸LL B.水準盒軸L′L′∥豎軸VV C.十字線橫線∥豎軸VV D.十字線縱線∥豎軸VV
A.①③⑤ B.②④⑧ C.③⑤⑦ D.②③⑧
A.后視讀數(shù) B.前視讀數(shù) C.水準尺讀數(shù) D.中視讀數(shù)