After mining, to reclaim the land, the depression is filled with rocks then the top is filled with loosely graded soil. Introduction of early succession plants is important before big trees can grow. The early succession plants help in the breaking down of the rocks into soil hence making the topsoil deeper to support trees.
Answer:
The valves' main job is to keep the blood moving in one direction – back up towards the heart. When the valve is open, blood freely flows upward towards the heart and when the valves are closed, blood cannot flow back
<span>B. Evaporation, precipitation, run off, lake storage</span>