Charles's Small Engine Repair Shop, a proprietorship, started the year with total assets of $50600 and total liabilities of $31500. During the year, the business recorded $121000 in repair revenues, $71700 in expenses, and Charles Simpson, the owner, withdrew $18600. Charles's capital balance changed by what amount from the beginning of the year to the end of the year? $19100. $30700. $37400. $6700