Answer:
Faciliated diffusion, which requires a carrier protein but no cellular energy. The energy for this process is provided by the concentration gradient of the substance being transported.
The rods originally contain the fuel for nuclear reactions, which mean they are highly radioactive. The radiation they emit is very dangerous and harmful to all types of life; therefore, they must be handled with care and disposed of properly to minimize damage because of them.
It would be easier to put an image instead of explaining it. Here you are!
R = Red
r = white
RR = 25% - 25% chance of red
Rr = 50% - 50% chance of pink
rr = 25% - 25% chance of white