______拍卖公告应当至少在______20日发布。
参考答案：国有土地使用权 拍卖日前
It must be kept in mind that ____ lifelong study can you survive in the highly competitive society. [ ]
A. only when
B. until then
C. only through
D. until when
引起储量增减变化的原因有（）。
A.补充勘探
B.采勘对比
C.井界变动
D.重算
E.报损
