If I took a tree apart down to its chemicals, what would it mostly be made of

Much of the general structure and physical properties of the interior of the earth are inferred from: a)deep oil and gas bore holes b)geologic investigations c)analysis of seismic waves d) study of volcanoes

Describe at least two advantages and two disadvantages of using hydropower as a source of energy.

Why is the bottom layer of a trophic pyrimid the