Using 2018 Annual Report for Dollar General pages 41-68 (it is public information and can be found online by googling. Chegg does not allow me to add the link)

Corporations must disclose the depreciation method(s) used to value property and equipment. In some cases, corporations will use more than one depreciation method. What method does Dollar General use to depreciate land improvements and over how many years?

b. straight-line over 39-40 years

c. double-declining balance over 3-10 years

a. straight-line over 20 years

d. land improvements are not depreciated