#1. How long was Joe Louis Heavyweight Champion?

Louis won the Heavyweight title in June 22, 1937, in Chicago, by knocking out James J. Braddock, and retired undefeated as champion on March 1, 1949. So roughly 11 years and 8 months.

#2. In what division, and at what weight did Oscar De La Hoya begin his pro boxing career?

Marble got this right, Oscar started his pro career as a Lightweight (135) but moved down to Super-feather (130) for 1 fight.

#3. Who did Jack Johnson win the Heavyweight title from?

From Tommy Burns, in December 1908, at Rushcutter's Bay Stadium, Sydney, New South Wales, Australia. Johnson kept the Heavyweight title until April 1915, losing it to Jess Willard in Havana, Cuba.

#4 Big George Foreman won the Heavyweight Crown by a 2nd round KO from Joe Frazier in January 1973, how many times did Foreman defend the title and how long was he Heavyweight Champion before losing it to Muhammad Ali?

After winning the Heavyweight crown from Frazier, Foreman defended it twice, against Jose Roman, (KO 1) and then Kenny Norton, (KO 2) pulverizing both guys in the process. Foreman held the HW title, for roughly 1 year and 9 months before losing it to Ali in Oct. 1974.