Prepare adjusting entries for the following items on December $31,$ the end of the fiscal year for ABC Company. The company initially records cash received in advance of performing the service as a liability, and prepaid expenses as current assets.

a$)$ Amortization on equipment, $$2,500$

b$)$ Services performed but unbilled, $$3,500$

c$)$ Salaries owed to employees at year end, $$2,500$

d$)$ Unearned service revenue earned, $$5,500$

e$)$ Supplies used during the year, $$3,200$

f$)$ Prepaid rent expired during the year, $$7,500$