April 1Sold merchandise for $4,000, with credit terms n/30; invoice dated April 1. The cost of the merchandise is $2,400.April 4The customer in the April 1 sale returned $480 of merchandise for full credit. The merchandise, which had cost $288, is returned to inventory.April 8 Sold merchandise for $1,500, with credit terms of 1/10, n/30; invoice dated April 8. Cost of the merchandise is $1,050.April 11 Received payment for the amount due from the April 1 sale less the return on April 4