if $1560 was received in january for services perdormed in january, what was the balance in unearned revenue at december 31,2023?

SAGE HILL COMPANY Adjusted Trial Balance (Partial) January 31, 2024 \begin{tabular}{lrr} & Debit & Credit \\ \hline Supplies & $830 \\ Prepaid insurance & 1,280 \\ \hline Equipment & 7,200 \\ Accumulated depreciation-equipment & & \\ Salaries payable & \\ Unearned revenue & \\ Service revenue & \\ Depreciation expense & & \\ Insurance expense & 600 \\ Salaries expense & 320 \\ Supplies expense & 1,800 \\ \hline \end{tabular}