8 (1994, 1997, 1998, 2000, 2002, 2003, 2004 (captain), 2005 (captain))
once
20 times, the most by any team.
7x.
it's only been changed once
Once, 2005.
As many times as the player's major league club desires.
wang wang wang
As many times as they want.
Greg Norman won the Australian Open five times: 1980, 1985, 1987, 1995, 1996
Rafael Nadal has won the Australian Open on one occasion - this coming in 2009, where he defeated Roger Federer in the final.
As long as the player has not fouled out, they may come into the game as many times as the coach wants them to.
2 years 2011 and 2012 current champions