On April $1,$ Helen Martin established Martin's Travel Agency. The following transactions were completed during the month$\mathrm{.}1.$Invested $$13,000$ cash to start the agency$\mathrm{.}2.$ Paid $$600$ cash for April office rent$\mathrm{.}3.$ Purchased equipment for $$2,200$ cash$\mathrm{.}4.$ Incurred $$600$ of advertising costs in the Chicago Tribune, on account$\mathrm{.}5.$ Paid $$900$ cash for office supplies$\mathrm{.}6.$Performed services worth $$11,000$: $$2,800$ cash is received from customers, and the balance of $$8,200$ is billed to customers on account$\mathrm{.}7.$ Withdrew $$400$ cash for personal use$\mathrm{.}8.$ Paid Chicago Tribune $$400$ of the amount due in transaction $(4)\mathrm{.}9.$Paid employees' salaries $$2,200\mathrm{.}10.$ Received $$5,200$ in cash from customers who have previously been billed in transaction $(6).$