Why are the troposphere and the stratosphere important to human survival?

How does rain water cause erosion and deposition? a. when acidic water soaks into the ground, water dissolves limestone, resulting in the formation of caves.b. when a river overflows it moves downhill resulting in the formation of caves.c. when it rains, water flows into rivers and streams and moves back to land, resulting in the formation of caves.d. when water empties into lakes, sediment is deposited, resulting in formation of caves.

With these question would be nice i needs them in a hurry which nation leads eastern europe in nuclear energy usage? a ukraine b lithuania c slovakia d solvenia which eastern european nation is popular with skiers? a czech republic b estonia c bulgaria d none are

Witch are features of the social democracy that is common in europe