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1 下圖中公制分厘卡的讀值是
A 12.18mm
B 12.67mm
C 13.18mm
D 13.68mm
襯筒的刻度值12.5mm,外套筒的刻度值0.17mm,此分厘卡的讀值為12.5+0.17=12.67mm