Potential difference of 2 points across charge and conductor

[leachlife4]

Homework Statement

See attached image.

Homework Equations

Potential difference over a line:
V=\int E dl

The Attempt at a Solution

I assume that the approach to take would be to divide up the problem into different parts, and simply add them together.
\int E dl

I am a bit unsure on what to do with the conductor though, do I simply subtract the distances and get something like
\int^{b-h}_{0} E dl

Edit: sorry I don't know what the TeX tags are here...

 

[supratim1]

for the conducting slab, potential at both faces will be equal, as if it was nonexistent.