Refer only to the periodic table on the inside front cover, and arrange the following ionization energies

Question:

Refer only to the periodic table on the inside front cover, and arrange the following ionization energies in order of increasing value: the first ionization energy of F; the second ionization energy of Ba; the third ionization energy of Sc; the second ionization energy of Na; the third ionization energy of Mg. Explain the basis of any uncertainties.

Period Main-Group Elements 1 2 4 5 11 3 Na 6 IA 7 1 H 1.00794 3 Li 6.941 19 K 39.0983 12 Mg 22.98976928