Following Is a List of Account Balances of Wilson Mowing

Following is a list of account balances of Wilson Mowing Services as of December 31 of the first year of operation:
$$\begin{array} { | l | r | } \hline \text { Accounts receivable } & \$ 2,500 \\\hline \text { Accounts payable } & 3,500 \\\hline \text { Salary expense } & 4,500 \\\hline \text { Repairs expense } & 800 \\\hline \text { Truck } & 8,500 \\\hline \text { Equipment } & 6,300 \\\hline \text { Notes payable } & 8,200 \\\hline \text { Cash } & 6,800 \\\hline \text { Supplies expense } & 1,600 \\\hline \text { Service revenue } & 31,900 \\\hline \text { Gasoline expense } & 3,800 \\\hline \text { Salary payable } & 200 \\\hline\end{array}$$ Calculate the net income.

A) $21,200
B) $11,900
C) $12,200
D) $24,100