Retirement of plant assets. Suppose that Neptune Equipment Corporation acquires a new machine used in manufacturing for $\$ 9,600$ on July 1, Year 4. It estimates that the machine will have a useful life of four years and a salvage value of $\$ 1,600$. The company closes its books annually on June 30.

a. Compute the depreciation charges for each year of the asset's life assuming the straight-line method.

b. The firm sells the machine for $\$ 2,700$ on September 30, Year 7. Give the journal entries on this date.

c. Repeat part

b, but assume that the firm sells the machine for $\$ 2,700$ on December 31, Year 7.