I know, I know...! ;) But maybe someone else will guess... Hint: the artist who painted it is Polish, the man depicted is too, I suppose, but this art work is inspired/a copy of a painting by a famous foreign painter.
Liceum used to be 4 years, then 3 and now again 4.
It is/was a bit different with
licea plastyczne - typically they used to be usually 5 years, sometimes 6, for example, and later it changed to 4 or 6 (or both in one school).