Select the items from the following list that can be classified as a current liability, non-current liabilities, a provision or a contingent liability.

Accounts payable

Unearned revenue

Accrued revenues

Accrued expenses

Provision for warranty repair costs (1 year)

20 - year debentures

Mortgage payable (30 years)

Accumulated depreciation

Allowance for doubtful debts

Income tax payable

An unresolved lawsuit against the entity for copyright infringement

Environment damage that an entity has undertaken to repair