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Required information [The following information applies to the questions displayed below.] The following are the sales transactions of EcoMart Merchandising. EcoMart uses a perpetual inventory system and the gross method. October 1 Sold merchandise for $1,500, with credit terms n/30, invoice dated october 1 . The cost of the merchandise is $900. October 6 The customer in the october 1 sale returned $150 of merchandise for full credit. The merchandise, which had cost $90, is returned to inventory. October 9 Sold merchandise for $700 cash. Cost of the merchandise is $450. October 30 Received payment for the amount due from the October 1 sale less the return on october 6. Use the above transactions, to analyze each transaction by indicating its effects on the components of the income statementspecifically, identify the accounts and amounts (including + or ) for each transaction