The annual financial statements of Valley Vineyards, Inc. include the following footnote:

The average useful life of Valley's depreciable assets at the end of its year is:

Select one:

a$.$ None of these are correct.

b$.18\mathrm{.}2$ years

c$.17\mathrm{.}2$ years

d$.14\mathrm{.}7$ years

e$.24$ years