rhino pls
electrons in orbitals can't be too confined due to the uncertainty principle, so as principle quantum number n increases, the electron orbitals must be spread further from the nucleus (as n increases, the atomic radius increases) .
Additionally, inner electrons of lower azimuthal quantum numbers will shield higher orbitals (electrons will repel other electrons), and further decrease nuclear attraction. So you can use this to deduce titanium will have a atomic radius smaller than polonium.