was he a singer too?
Yes, started as a singer on radio
Merv Griffin
Griffin started as a singer on radio at age 19, appearing on "San Francisco Sketchbook", a nationally syndicated program based at KFRC. 
how much can you wager in final jeopardy 13, 420, and 911 who developed it? Merv Griffin how many levels does it have? Three is it a game that can be played on a given platform? It is a television game show featuring a quiz competition who hosts it? Alex Trebek what does the winner get? They are paid their winnings in cash which channel does broadcast it? NBC what it stands for? National Broadcasting Company when was it established? 1926 which stations did it start with? WEAF and WJZ what is the former about? A commercial AM radio station and the flagship station of the NBC Radio Network does it telecast any programme for children? UNANSWERABLE which countries does it have it's presence? New York City was the show received well? It has won a record 39 Daytime Emmy Awards how does the set of it look like? Ggame board was exposed from behind double-slide panels and featured flipping panels with the dollar amount on one side and the clue on the other did it have any background score? Yes who composed it? Mery Griffin where is he from? San Mateo, California
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Merv Griffin [SEP] Singing
Griffin started as a singer on radio at age 19, appearing on "San Francisco Sketchbook", a nationally syndicated program based at KFRC. Griffin was overweight as an adolescent and a young man, which disappointed some radio fans when they saw him in person. He wrote years later in his autobiography that originally there was a deliberate effort to keep the public from finding out how he looked. Embarrassed by the weight issue, Griffin resolved to change his appearance, losing 80 pounds in four months. Freddy Martin heard him on the radio show and asked Griffin to tour with his orchestra, which he did for four years.