Find the mean time between collisions in a wire

[smashyash]

Homework Statement

I am to find the mean time between collisions of electrons in a wire and am having a difficult time manipulating equations with known variables. I am given values for E, J, n and rowe.

Homework Equations

v = (qT/m)*E
rowe = E/J
J = nqv

The Attempt at a Solution

I have tried every possible combination of ways to manipulate this equation but I guess my problem is q. I don't think I know the value or can assume it and I can't cancel it out anywhere!

 

[sgd37]

isn't it just the charge of the electron (1.6 x 10^-19 c)

the greek letter is rho not rowe