Write the uses of isotopes used for treatment of cancer ?!?!

Matches the chemical name of each oxide of phosphorus to its chemical formula

What’s the scientific notation for the number 6,840,000,000

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?