21. an electron is excited to a higher energy level with 5.3 units of energy. when it relaxes to the ground
state, the emitted photon will have which of the following energies?
a. greater than 5.3 units
b. 5.3 units
c. less than 5.3 units
d. some integer multiplied by 5.3 units

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