A.1/2000 B.1/3000 C.1/1000 D.1/4000
A.正數(shù) B.負數(shù) C.零 D.小數(shù)
A.對中一整平一瞄準一讀數(shù) B.對中一瞄準一整平一讀數(shù) C.瞄準一整平一對中一讀數(shù) D.瞄準一對中一整平一讀數(shù)