What is the answer to this?

In the month of May, a company wrote checks in the amount of $66600. In June, checks in the amount of $91138 were written. In May, $60970 of these checks were presented to the bank for payment and $78358 in June. What is the amount of outstanding checks at the end of May assuming that there were no checks outstanding on April 30 ? \begin{tabular}{|l|l|} \hline$12780 \\ $25560 \\ $5630 \\ $18410 \\ \hline \end{tabular}