Stetson University teaches a large range of undergraduate courses. It is interested in determining the cost equation for the facilities cost as a function of student credit hours so that it an more accurately budget its facilities costs as enrollment grows. Information for the high and low cost semesters and volumes for last 5 years appears below Semester Student Credit Hours Facilities Cost Spring 2007 250,000 $500,000 Fall 2004 300,000 $530,000 Using the high low method, with student credit hours as the activity driver, what is the equation for facilities cost (FC) as a function of student credit hours?