Use the following information for questions $15$ and $16.$

Link Co$.$ purchased machinery that cost $$810,000$ on January $4,2009.$ The entire cost was recorded as an expense. The machinery has a nine$-$year life and a $$54,000$ residual value. The error was discovered on December $20,2011.$ Ignore income tax considerations.

$15.$ Link's income statement for the year ended December $31,2011,$ should show the cumulative effect of this error in the amount of

a$.$ $$726,000.$

b$.$ $$642,000.$

c$.$ $$558,000.$

d$.$ $$0.$

$16.$ Before the correction was made, and before the books were closed on December $31,2011,$ retained earnings was understated by

a$.$ $$810,000.$

b$.$ $$726,000.$

c$.$ $$642,000.$

d$.$ $$558,000.$