Strontium-90 (Sr-90) has a half-life equal to 28.1 years. How much of a 100 gram sample of strontium-90 will remain after 56.2 years

An electron moved from shell n = 2 to shell n = 1. what most likely happened during the transition? a fraction of a photon was added. a photon of energy was absorbed. a fraction of a photon was removed. a photon of energy was released.

Glucose (c6h12o6) is an important biological molecule. (round the answer to nearest hundredth.) what is the percent by mass of carbon in glucose?

28. which is not a reason that water is used to store spent fuel rods from nuclear power plants? water increases the speed of the chain reaction in the fuel rods. water protects nuclear power plant workers from the high temperature and radiation of the fuel rods. water acts as a radiation shield to reduce the radiation levels. water cools the spent rods. salts action