正常地层压力下，机械钻速随井深的增加而（），d指数随井深的曾加而（）。
参考答案：减少；增大
The manager of the company told us that very little ______ was made of the waste material in the past. [ ]
A. cost
B. value
C. matter
D. use
批判教育学的主要观点是
