Is your mother a teacher _________ a doctor?[ ]
A. and
B. but
C. or
答案:C
成年男性血红蛋白的正常值范围是哪一项 ( )
A.60~100g/LB.90~120g/LC.100~140g/LD.110~150g/LE.120~160g/L
门窗工程安装合页时,必须按画好的合页位置线开凿合页槽,槽深应比合页厚度大()
A、1~2mm
B、2~3mm
C、1~3mm
D、3~5mm