单项选择题
A.1%,0.2%B.0.2%,1%C.1%,0.3%D.0.3%,1%
A.5%,10%B.10%,5%C.10%,15%D.15%,10%
A.镊子钳摩擦B.刮刀轻刮C.W14-W28号金相砂纸轻砂D.酒精棉擦洗