Which element’s symbol could replace the question mark in the diagram?

Skills of homo sapiens were found an excavation. the skulls were preserved because the bodies were frozen. so, these fossils are (blank) fossils.the image shows the evolution of skulls beginning 2 to 3 million years ago. based on the image, modern human skulls(blank) ape skulls.

Under which circumstances are kp and kc equal for the reaction aa(g)+bb(g)⇌cc(g)+dd(g)?

What does an electron configuration for an atom relate to the atoms placement on the periodic table