Rivers Corp., which sponsors river tours, adjusts and closes it accounts each December 31. The following situations require adjusting entries at the current year-end.

1. Equipment is to be depreciated for the full year: cost is $67,500, and the estimated useful life is five years.
2. The accounts receivable balance at December 31 is $12,000. The company estimates that 3% of receivables will not be collected. (Assume a zero beginning balance in the allowance for doubtful accounts.)
3. Property taxes for the current year have not yet been recorded or paid. A statement for the current year was received near the end of December for $6,000; if paid after February 1 in the next year, a 10% penalty is assessed.
4. Office supplies that cost $600 were purchased during the year and debited to Supplies. A physical count of inventory showed $150 of supplies at the prior year-end and $225 at the current year-end.
5. Rivers received $15,000 cash for 12 monthly tours to take place evenly from September of the current year to August of next year. The total amount collected on September 1 of this year was credited to Service Revenue.
6. Rivers received a note receivable from a customer dated November 1 of the current year. It is a $9,000, 10% note, due in one year. At the maturity date, Rivers will collect the amount of the note plus interest for one year.
7. Salaries earned from December 29 through 31 of this year, but not yet recorded or paid, are $7,200.
8. Interest expense of $600 incurred, but not yet recorded, for November and December of this year will not be paid until April 30 of next year.

Prepare the necessary adjusting journal entries on December 31 for each situation. Assume that no adjusting journal entries were recorded during the year prior to year-end.

Note: Round your answers to the nearest whole dollar. For example, enter 50 for 50.49 and enter 51 for 50.5.