How can the period,group,and block of an element be predicted?

(N/A) The period of an element corresponds to the principal quantum number $(n)$ of the valence shell.
The block of an element is determined by the orbital into which the last electron enters.
The group number is determined by the number of valence electrons for $s$-block and $p$-block elements,or the sum of $(n-1)d$ and $ns$ electrons for $d$-block elements,where $n$ is the principal quantum number of the valence shell.