影响爆破效果的岩石物理性质主要有（）、（）、（）和（）等。
参考答案：密度；孔隙率；波阻抗；风化程度
Could you tell us _____ yesterday?[ ]
A. what do they do
B. what did they do
C. what they did
D. what they do
如何进行评估考核？
