The construction is aqueducts
After looking at the photograph given above, one sedimentary rock that probably metamorphosed to form rock on unit 6 is called limestone. You can also use the sedimentary rock called dolostone. Both will be acceptable answers to this question.
Nuclear fusion generates the energy that is released by stars.
In the great majority of stars, it's the fusion of hydrogen nuclei
to form helium nuclei plus energy. In very old stars, the nuclei
of heavier elements are fused, forming even heavier ones.
The answer is C
the continental crust is mostly granite while the oceanic crust is mostly basalt