A.外移0.007m B.內(nèi)移0.007m C.外移0.003m D.內(nèi)移0.003m
A.18.0063m B.17.9937m C.18.0126m D.17.9874m
某鋼尺的尺長(zhǎng)方程式為:L=30-0.003+1.25×10-5×30×(t-20℃),若用其在4℃的溫度下丈量了60米,則其溫度改正數(shù)和實(shí)際長(zhǎng)度分別為()。
A.-0.012m;59.988mB.+0.012m;60.012mC.–0.012m;59.982mD.+0.012m;59.982m