3. consider that breeder reactors are to be built using 233u (obtained from 232th) and 239pu, respectively. a. what is the maximum conversion ratio that could be achieved in principle with each fuel? (assume that the reactor consists of pure fuel and that no neutrons escape from it.) b. what factors cause real-world conversion ratios to be lower than the values you calculated in part a? c. explain why "reactor grade" plutonium is not desired for use in a weapon.