During the current year, Danny, a calendar-year taxpayer, acquired and placed in service the following business assets:

January: Delivery trucks $ 50,000

March: Warehouse building 150,000

June: Computer system 30,000

September: Automobile 30,000

November: Office equipment 90,000

Which convention(s) is(are) used to figure Dannys depreciation for the current year and why?

a. mid-quarter for all assets except the warehouse building, which uses mid-month

b. half-year for all assets

c. mid-quarter for all assets

d. half-year for all assets except the warehouse building, which uses mid-month; half-year for the automobile and the office equipment