What is the meaning of metal oxide

Which of the following is true for the actual yield of a reaction? it is always calculated as a ratio. it is the yield from the excess reactant. it is the yield from the limiting reactant. it is always less than the theoretical yield.

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?

Stage in which a typical star has completely stopped fusion