There are four layers in the atmosphere. most human activities take place in the select one of the options below as your
a. stratosphere
b. troposphere
c. mesosphere

Most of human activities are concentrated in the lowest part of the Atmosphere: the Troposphere: the correct answer is: b).

Our planes also fly in Troposphere, but our flying baloons also reach the next layer: in the stratosphere. After this layer the next layer is the Mesosphere - where the Meteors can be found.

Answer (d) may increase or decrease porosity through dissolution or deposition;

Answerhurricanes;