I had hoped to visit the gallery before I left Florence, but it's closed on Monday.
Q1 : Shouldn't it be it was closed ?
Q2 : Does present simple Imply more definite sense ? I mean "it is closed" imply that It has been closed on Monday from the Ice-age to the current moment !
Q3: Is it grammatical to use tenses in above sequence, Past Perfect, Past Simple and Present ?
It must be noted the highlighted sentece belong to cambridge grammar book.