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If you chip a tooth, most likely you will go to the dentist to have the missing material filled in. currently the material used to fill in teeth is a polymer that is flexible when put in, yet is hardened to the strength of a tooth after irradiation with blue light at a wavelength of 461 nm. what is the energy in joules for a photon of light at this wavelength?

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.

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?