While bulking, I'll usually keep reps in the 6-8 range on most (not all) exercises. How many sets to do is dependent upon your body chemistry and ability to recover. It's going to vary from person to person. If you've worked out for any length of time, you should have some inclination as to how many sets your body best responds to. Generally while on cycle, I'll do slightly more sets (maybe 15-20% more).

Whether you gain abdominal fat depends on your metabolism rate, how clean your calories are, and how much cardio you do. If you are bulking you have to expect to gain atleast some fat. That's just how it goes...

You should be doing cardio anyways, 2 times a week is fine when bulking IMO. Just to keep some of the fat off and more importantly keep your cardiovascular system healthy.

Like HHM said, how much fat you gain depends on how much you eat. Start at around 3000-3500 cals a day, and increase it by 500cals a week if your not gaining. Then take it back 250-500 cals if you think your gaining too much fat.

I like to keep my reps between 6-12, it really depends on the exercise and how I feel. For compounds lifts I go heavier with lower reps, but for isolation exercises I go a little higher, same thing for dropsets/supersets.

I think diet has alot more to do with bulking compared to reps.

Alot depends on the excersize your doing. I like lower reps for most core r heavy lifts and higher for assistance excersizes.

thanks