Electrostatics problem

[zimo]

1. The problem statement, all variables and given/known data
The problem is attached as an image.

2. Relevant equations

R=integral(rho*D/A)
I guess that there is more...

3. The attempt at a solution

I got stuck stright on A), for I don't have a clue what to do with such a weird Rho value.
Afterwords when we want to find E field - can't we just say E=v0/D ?

[sp1408]

Choose a starting radius,the angle r(instead of theta) is the angle in the cos term,divide the cylinder into different anglular elements of angle dr,each of these has an area 1/2*a*a*dr and a length D,Each on has a resistance of rho*D/Area where the formula for rho in terms of angle is given,,all such elements are connected in parallel,take the reciprocal and integrate r from 0 to 2pi,then reciprocate the answer to get the restistance.