Performed services for patients who had dental plan insurance. At january 31, $920 of such services was completed but not yet billed to the insurance companies. 2. Utility expenses incurred but not paid prior to january 31 totaled $610. 3. Purchased dental equipment on january 1 for $85,850, paying $28,150 in cash and signing a $57,700, 3-year note payable (interest is paid each december 31). The equipment depreciates $550 per month. Interest is $690 per month. 4. Purchased a 1-year malpractice insurance policy on january 1 for $24,000. 5. Purchased $2,340 of dental supplies (recorded as increase to supplies). On january 31, determined that $670 of supplies were on hand