Equipment with a cost of $$777,000$ has an estimated residual value of $$77,000,$ has an estimated useful life of $25$ years, and is depreciated by the straight$-$line method.

a$.$ Determine the amount of the annual depreciation.

fill in the blank $1$ of $1$$

$28,000$

b$.$ Determine the book value after $12$ full years of use.

$?$

c$.$ Assuming that at the start of the year $13$ the remaining life is estimated to be $17$ years and the residual value is estimated to be $$84,000,$ determine the depreciation expense for each of the remaining $17$ years.

$?$