I probably average around 1/week. More recently around 3/week and this week I had to give my first ever red.
As many as i need to. I usualy give reps to funny posts, helpful posts and people I deal with. I never gave a red and I hope i won't have to
It depends on the quality of posts. If I see something helpful I do give a rep to the member - 11-20 a week I'd say.