Given the Table Below, Indicate the Impact of the Following

Given the table below, indicate the impact of the following errors made during the adjusting entry process. Use a "+" followed by the amount for overstatements, a "-" followed by the amount for understatements, and a "0" for no effect. The first one is done as an example.
Ex. Failed to recognize that $600 of unearned revenues, previously recorded as liabilities, had been earned by year-end.
1. Failed to accrue salaries expense of $1,200.
2. Forgot to record $2,700 of depreciation on office equipment.
3. Failed to accrue $300 of interest on a note receivable.