（）破碎机的工作原理是利用高速旋转的铁锤对物料产生打击、冲击、剪切和研磨而将物料粉碎的。
参考答案：锤式
75. Taiji boxing is good _____ health, so the old man began to practise it ten years ago and now he is good _____ it.
A．for; to
B．to; for
C．for; at
D．at; for
交强险每次无责事故死亡伤残赔偿限额为（）
A.8000
B.10000
C.15000
D.20000
