An average biceps size for teenagers would be anywhere from 11.5 to 12.5 inches.

Yes. Anything above 15-inch biceps is considered big.

Four to eight sets of bicep exercises a week are more than enough to build bigger biceps.

There is no precise answer to this question as there are numerous factors at play here, from supplementation, steroid use, the intensity of weight...

Excluding Synthol lovers, there are a few who have measured their biceps at 24-inches, including legends like Ronnie Coleman and Eddie Hall.