The following items represent common postacquisition expenditures incurred on machinery:
a. Lubrication service
b. Painting costs
c. Cleaning expenditures
d. Rewiring costs to increase operating speed
e. Repairs
f. Replacement of defective parts
g. An overhaul to increase useful life
h. Cost of a muffler to reduce machine noise
i. Costs of redesign to increase output
Identify each item as a betterment or a maintenance item.