Double helix used in a simple 9th grade level sentence and one fact

What are four key elements of the study of economics?

Put the following steps of the convection process in the correct order. 1. gravity pulls cooler matter downward. 2. the matter expands and decreases in density. 3. an up-and-down flow of matter produces a convection current. 4. matter is heated. 5. warmed matter is forced upward. question 2 options: a) 4, 2, 5, 1, 3 b) 2, 4, 3, 1, 5 c) 3, 2, 5, 4, 1 d) 1, 4, 2, 5, 3

And give a detailed description! scientist observes the boundary between two tectonic plates for a decade and finds that no new volcanoes have formed over the course of her investigation. does this result support the theory of plate tectonics? why or why not?