Finding capacitance per unit length

[tnutty]

Homework Statement

You are planning to install a home video studio. A very important piece of information is missing from the specifications. You must find the capacitance per unit length for a coaxial cable. The cable has an inner radius of 2.0mm and an outer conductor 4.0mm in radius separated by polyethylene insulation that acts as a dielectric, with it equaling to 2.3.

What's the capacitance per unit length?

The dielectric is 2.3 according to my book.

I am not sure how the setup for this problem should be.

 

[Mark44]

You omitted the section about relevant formulas and equations. Do you have any formula for the capacitance of a coax conductor?