Myra purchases a refrigerator from Howard Appliances for $800 for use in her home. Myra pays $200 down and signs an installment sales contract with Howard Appliances to finance the $600 balance. The installment sales contract provides that Myra will pay $50 per month until the $600 balance, plus five percent interest, is paid in full. To perfect its security interest in the $600, Howard must: file a financing statement with the appropriate government office. do nothing. file the installment sales contract with the secretary of state. file the installment sales contract with the county clerk