Israel's diverse culture stems from the diversity of its population: Jews from diaspora communities around the world have brought their cultural and religious traditions back with them, creating a melting pot of Jewish customs and beliefs. Israel is the only country in the world where life revolves around the Hebrew calendar. Work and school holidays are determined by the Jewish holidays, and the official day of rest is Saturday, the Jewish Sabbath. Israel's substantial Arab minority has also left its imprint on Israeli culture in such spheres as architecture, music, and cuisine.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): Work and school holidays are determined by what?
Jewish holidays