The best cost driver for spa operating expenses is measured by Patron-Days of Stay. The following are the data on the days patrons stayed at Monterey Resort and Spa and the spa operating expenses for the most recent eight months:

Patron-Days Spa Operating

of Stay Expenses

April 40 $1,400

May 36 1,150

June 38 1,210

July 15 650

August 21 870

September 24 920

October 28 975

November 18 740

1. Determine the variable cost rate per patron day of stay.
2. Determine the fixed cost for the period.
3. Show the cost function equation by specifying patron day of stay and spa operating expense.