Write a MATLAB function that will determine the density of tribromoethylene in units of kilograms per cubic meter when a cylindrical tank filled to a specific height $($measured in feet$)$ with tribromoethylene has been pressurized to the provided value of pressure $($measured in atmospheres$).$ For example, you might test this function with a height of $25$ feet, a surface pressure of $3$ atmospheres, and a total pressure at the bottom of the tank of $5$ atmospheres.

Name your function Dens.