Mortgage Payable - Classified Balance Sheet?

I'm making a classified balance sheet for my homework assignment, and I'm a bit perplexed on how to write this in the sheet :

"$30,000 of the mortgage payable is due to be paid next year"

The only information I have from the beginning :

-Worksheet for the year ended December 31, 2014 containing the trial balance and the adjusted trial balance.

-Mortgage payable at the trial balance and adjusted trial balance show as $120,000.

-Interest expense and interest payable at the adjusted trial balance show as $10,000.

-Liabilities : Accounts payable, Unearned Rent Revenue, Mortgage Payable and Interest Payable.

I only know to write $90,000 from the original Mortgage Payable to "Long-term liabilities", and $30,000 from the original Mortgage Payable to "Current liabilities", but do I put the 30k in the Interest Payable account or do I need to make another account, and if so, what's the title?