A.20mm B.40mm C.60mn D.120mm
A.水準(zhǔn)儀的視準(zhǔn)軸和水準(zhǔn)管軸不平行 B.支架放在松軟土上,時(shí)間長(zhǎng)了儀器下沉 C.調(diào)平?jīng)]調(diào)好 D.風(fēng)吹動(dòng)望遠(yuǎn)鏡
A.0.5m B.1m C.1.5m D.2m