如图所示;用游标深度尺测得55°的燕尾槽的深度是40mm,用直径为30mm的圆棒做测量棒,测得两圆棒之间的距离为20.40mm,求燕尾槽槽底A和槽口B的宽度()。
A.102.36mm,56.17mm B.115.40mm,53.80mm C.77.60mm,48.20mm D.108.03mm,52.02mm