Which concept is described in the theory proposed by Hess?

Continents do not move.
Cool rock pushes through the crust.
Trenches are sites of seafloor spreading.
Mid-ocean ridges are sites of seafloor spreading.

Wind energy is plentiful in regions with vast open spaces it is a non polluting renewable resource what could be an economic factor that makes the use of this resource less feasible then non renewable resource even in such regions

Name one similarity and one difference between the morphology of a brachiopod and a bivalve

Astudent reads the following text in a science book: scientific evidence tells us that the cause of earths four seasons is the tilt of earth as it revolves around the sound the student is instructed to illustrate this information in a science book. how will the student illustrate winter in the northern hemisphere? a.earths northern hemisphere will tilt away from the sun. b. earths northern hemisphere will tilt toward the sun. c.earths orbit will be farther away than from the sun d. earths southern hemisphere will tilt away from the sun.