Computing Depreciation, Net Book Value, and Gain or Loss on Asset Sale

a$.$ At the disposal date, what is the $(1)$ cumulative depreciation expense and $(2)$ net book value of the plane?

$(1)$ Cumulative depreciation expense $$0$

$(2)$ Net book value

b$.$ How much gain or loss is reported at disposal if the sales price is:

Note: Do not use a negative sign with your answers.

$\backslash$table$[[,$Sales Price,Gain or Loss,$],[1.,$A cash amount equal to the plane's net book value.,$$,$hat$(AA)$