RhondaChoate

I just received a Sulcata Tortoise from my niece, she's had him since he was the size of a half dollar, she believes he is now 5yrs old. This is my first Tortoise so I'm trying to learn as much as possible, for instance, how can I tell exactly how old he is, how can I tell if he is a he. Is he the right size for his age, and this is my first time on here also.