Lynch Company owns and operates a delivery van that originally cost $46,400. Lynch has recorded straight-line depreciation on the van for four years, calculated assuming a $5,000 expected salvage value at the end of its estimated six-year useful life. Depreciation was last recorded at the end of the
fourth year, at which time Lynch disposed of this van .
a. Compute the net book value of the van on the disposal date.
b. Compute the gain or loss on sale of the van if the disposal proceeds are:
1. A cash amount equal to the van's net book value.
2. $21.000 cash.
3. $17,000 cash

explain how the selling of this van impacts the the accounting equation  in each of the selling situations in a and b.