Kater Company manufactures shelving units. The company receives pre-cut wood, drills holes in the wood so that movable shelves may be installed, then assembles and paint the units. Classify each of the following items of factory overhead as either fixed or variable cost.
a. Janitorial service (an outside service, not company employees)
b. Supervisor of the Drilling Department
c. Oil used to lubricate drill press machines
d. Propane for forklift trucks used to move the material from the Drilling Department to the Assembly Department
e. Natural gas used to heat the plant
f. Security guard
g. Drill bits used in the drilling department
h. Insurance on factory building
i. Electricity to power drill press machines
j. Rent of factory building