Stratosphere is the correct answer
60 years is three half life for the substance, so 40*1/2^3=5
Answer:
when the pores are completely filled in the rocks and soil
Explanation:
The zone of saturation is part of the divisions of ground water systems. It is the zone in which the pore spaces within the rock are completely filled with water.
The zone of saturation is where the aquifer lies in a body of water and it is the ground water prospect. Pore spaces can also be filled with hydrocarbons.
Above the zone of saturation is the water table. The water table defines the upper layer of the zone of saturation above which the pore spaces are filled with gas or no water can be found.
