Which choice lists one destructive and one constructive force that create new landforms? constructive: volcano; destructive: erosion
constructive: hurricane; destructive: earthquake
constructive: human activity; destructive: wind and water
constructive: weathering; destructive: landslides

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?

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

How many protons, electrons, and neutrons are in each of the following isotopes? a. zirconium-90 b. palladium-108 c. bromine-81 d. antimony-123