Many people may be tuning to television Friday evening for the final episode in which Alex Trebek hosts the game show "Jeopardy!" Trebek died in November of cancer . For all the years "Jeopardy!" has been on, and remember it existed before Trebek started as host, the program been a test of memory for both contestants and viewers. On the small chance you don't know how "Jeopardy!" is played, Trebek explained the rules at the beginning of the show. “You know how we play it. We provide the