Atoms of which two elements in the ground state contain the same number of valence electrons?

In an energy pyramid, which level has the most available energy?

1) describe the physical layout of the ocean floor ? 2) explain how the dumbo octopus swims differently than other octopus species and why this would be an advantage in the aphonic zone . 3) why are the types of organisms that live at each underwater hot vent so dramatically different ?

Light waves can move through , but they travel fastest when they move through a(n) .