Answer:
O-18 is used as a tracer in many hydrologic studies. It is most often used as a component in a mixing-model and hydrograph separation, as O-18 acts conservatively and is applied naturally and uniformly over broad areas. O-18 can be used when different sources (old water/new water) have different isotopic values.
Answer:
A.
Explanation:
I chose this because it seems more reasonable . Because its in the air so im guess that its gravitational bc to stay on top of a hill you need balance . Im sorry if its wrong k . I tried .
The cornea is the outer clear, round structure that covers the Iris and the pupil. The Iris is the colored part of the eye.
Atoms are combining to form molecules