American players are called 'imports.' Each team is allowed to field 12 players. There is no limit as to how many of the 12 can be imports.
No Maximum but a minimum of 20 canadians
CFL. It must be short for RoughRiders. There is no team called the "Riders" in the NFL. However, there is a team called the Raiders.
Ricky Williams played for the CFL Toronto Argonauts.
Montreal Alouettes
Only once, by Baltimore Stallions in 1995.
It has been announced that in 2014 the Ottawa Redblacks will become the ninth team in the CFL.
none
The teams that share a name between the NFL and CFL are the Detroit Lions of the NFL and the British Columbian Lions of the CFL.
They are all Americans only in the team.
There are nine home games and 1 home game presseason.
Montreal, 15