*practice
multiple choice
what processes are involved in the formation of igneous
rock?
chemical and physical weathering, deposition, and compression
changes in heat and pressure
melting and cooling
erosion and deposition

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.

Scientists discovered fossils in several layers of the earth you see here. they found fossils of algae, snails, and clams in layer d. given that information, where do you think they found fossil evidence of simple land plants and amphibians?

What is the largest environment on earth?