In League of Legends i'm Level 13 now and with Jax and like 18k Gold, lvl 18, i had 371 damage and attack Speed was 1.80.
I had Boots of Mobility, Trinity Force, Ravenous Hydra, Phantom Dancer, Infinity Edge and Blade of the ruined King. If you use every ability of Jax as offen as you can, you should be able to kill Baron Nashor.
Also i've got lvl 2 runes ...
In one long game, i just wahres to per the tune pass away, because it was a one on one staunst sehr as a bot. And at least i killed him like 4 times in the game.
Ps. In the end I killed Ashe (Bot) in like 1.4 seconds without any abilities.