Calculate surface mass density in the galaxy

[warfreak131]

Homework Statement

Suppose the number density of bright F dwarf stars at the Sun's radial distance from the Galactic center, varied with height above the galactic plane as:

n(z)=n0 exp(-z/h)

where h = 250 pc. Also suppose that the velocity dispersion of these dwarfs varies with z as $$\sigma_{z}^{2}=\sigma_{z_{0}}^{2}(1+\frac{z}{h})$$ where $$\sigma_{z_{0}}$$=14 km/s.

Show that the surface mass density within 1 kilo parsec of the plane is

$$\Sigma=90 M_{sun} / pc^{2}$$

Homework Equations

The Attempt at a Solution

I literally have no idea where to start, I've been working on this question for hours and have not gotten any progress. I've searched google top and bottom looking for an explanation. All I can find is research papers that give no derivation, or the websites use quantites and methods other than what is given to me in the question.

 

[BigJDubs]

I have a feeling that it has something to do with the Jeans equation but I don't really know how to go about it.Any help would be greatly appreciated.