The normal balance of liability account is Credit balance.

Normal balance is the side where the balance of the account is normally found. Asset accounts normally have debit balances, while liabilities and capital normally have credit balances.

 If the cost can never be zero, it has a fixed component. However, since it changes with the number of units produced, it also has a variable component. This is a mixed cost.

In accounting, the controlling account  is an account in the general ledger for which a corresponding subsidiary ledger has been created.

The balance sheet provides an overview of assets, liabilities, and stockholders' equity as a snapshot in time. The income statement primarily focuses on a company's revenues and expenses during a particular period.

Expenses means the cost incurred in or required for something.