单项选择题
A.热传导低B.抗冲击强度低C.体积收缩大D.需要特殊设备E.费用较高
A.3~4minB.4~6minC.5~7minD.6~8minE.8~10min
A.0.4mmB.0.6mmC.0.8mmD.1.0mmE.1.5mm