*45 POINTS*
don’t know if anyone gonna do this but worth a try to ask.

water is used to store them because it would keep the radiation from getting out in the open and causing harm to the workers

imma come back to you hold on

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.