Urinal system aka renal system
Answer:
1. Radiometric dating
2. Relative dating is used to determine the age of fossils or rock layers by by comparing it to similar rocks and fossils of known ages.
3. The youngest rock layers are at the top and the oldest are at the bottom, which is according to the law of superposition.
4. Tribolite and Pecten fossils
Fossils are used to determine the ages of rock layers. Index fossils are the most useful in determining relative aging. Index fossils are of organisms that lived for a short period of time. An index fossil allows a scientist to determine the age of the rock it is in. So if they are found in a particular age, it means they belong in that age.
5. Scientists commonly use radioactive dating methods by using radioactive decay cloak of certain elements such as potassium or carbon to date fossils or rocks.
6. Law of superposition because in terms of finding the age of the rock as an object, all that needs to be identified are the layers of the rock.
7. The nuclear decay of radioactive elements are a process that behaves in a clock-like fashion which makes it a useful tool for determining the exact age of fossils or rocks.
Answer:
Any combination of D, E and F
Explanation:
Since A, B, and C belong to different orders, and D, E and F belong to the same order, the latter are more closely related and thus are expected to show a greater degree of structural homology. They are closer to their common ancestor than A, B and C.
