Is a normal lifespan possible with hemophilia?

For many, yes. For those who have mild or moderate hemophilia, the answer is yes. For patients with severe hemophilia, the most recent data suggests about a 10 year shorter life span. It is important to remember, however, that the people analyzed for this study were initially treated in a much earlier era. Most likely this difference will become smaller the better we get at treating and preventing serious bleeds.
Probably. You must be under close doctor monitoring, and be sure to follow your regimen for treating any bleeding. In the past, because of contamination of the clotting factors with hepatitis, and HIV most people with hemophilia did not live a normal life span, but now the clotting factor replacement therapies are not contaminated.