I can't remember which atoms on the periodic table have larger radii than others. Can you help me with the following problem:

Question

I can't remember which atoms on the periodic table have larger radii than others.  Can you help me with the following problem:
Order Rb, Fr, Sb, and I from smallest to largest radius

Anonymous · Answer

I think it is I, Sb, Rb, Fr. Please confirm!

Shaniquaa · Answer

That is correct. The radius increases down and to the left of the periodic table