Rona Company is a calendar-year manufacturer. Rona is reviewing the following transactions for possible adjust- ing entries at December 31, 2020. 1. One of Rona Company's liabilities is a 12%, $40,000 long-term note payable, which requires interest to be paid each March 1 and September 1. 2. Rona Company owns a $20,000, 10% bond, which it purchased at face value and which pays interest each August 1 and February 1. 3. Rona Company performed and completed services for a customer in December for a $12,000 total fee. The customer was not billed and did not remit payment in the current year. The customer has a strong credit rating. 4. Depreciation of $30,000 is to be recorded. 5. Salaries totaling $15,000 were earned but not paid or recorded at year-end. The first payroll in 2021 is ex- pected to total $45,000. 6. Rona paid $4,800 cash for a one-year insurance policy on September 1, 2020. Rona records the full amount on September 1 as insurance expense. Required Prepare the adjusting entry (or entries) that are necessary, if any, on December 31, 2020, for each item 1 through 6