I think it is the C one because it depends on the type of construction in the area
Answer:
three half-lives
Explanation:
Converting 12.5% to decimal gives 0.125
If one half life is 0.5.
0.5*0.5*0.5 gives 0.125
Thus 3-half lives has been elapsed
Answer:
I believe the answer is C but i could be wrong
Answer:
Non point sources
Explanation:
A point source is usually a single known source of a pollution such as emission of toxic fluids from a company directly into water bodies.
Runoff of eroded soil and chemicals such as fertilizers and pesticides from cropland, feedlots, logged forests, urban streets, parking lots, lawns, and golf courses are examples of non point sources as there is no main known source of the pollution.