Which of the following items are properly classified as part of factory overhead for Ford Motor Company (F), a maker of heavy automobiles and trucks?

a. Air conditioner units for installation in vehicles

b. Consultant fees for a study of production line efficiency 

c. Dealership sales incentives

d. Depreciation on headquarters building in Dearborn, Michigan

e. Depreciation on mechanical robots used on the assembly line

f. Leather to be used on vehicles that have leather interiors

g. Machine lubricant used to maintain the assembly line at the Louisville, Kentucky, assembly plant

h. Plant manager’s salary at Buffalo, New York, stamping plant, which manufactures auto and truck subassemblies

i. Property taxes on the Dearborn, Michigan, headquarters building

j. Vice president of human resource’s salary