A.光學(xué)讀數(shù)裝置 B.指示表讀數(shù)裝置 C.基準尺 D.讀數(shù)標尺
A.0.01~0.02 B.0.01~0.03 C.0.02~0.03 D.0.02~0.04
A.90° B.75° C.60° D.45°