Black in color; contains dense rock with very small, well-formed crystals. What rock is this plzz help me

Why is it possible for different microorganisms to extract energy not only from carbohydrates and other biological molecules but from a large variety of substances?

Why must humans find substitutes for many minerals found on earth? (a) form at an extremely slow rate (b) controlled by other countries (c) too deep in the earth to collect

The lab procedure involves several factors, listed below some were variable and some were constant. label each factor below v for variable ot c for constant