The following expenditures were among those incurred by Jensen Corporation during the year ended December 31, 2019: Replacement of tiles on portion of roof that had been leaking $4,000 Overhaul of machinery that is expected to extend its useful life for another 2 years 6,000 How much should be charged to repairs and maintenance in 2019?

a. $0

b. $4,000

c. $6,000

d. $10,000