Answer:
As of March 31, there's a debt of $25,000
In April, $10,000 worth of merchandise is sold to Cars Inc. (with a COGS of $8,000)
Cars made a payment of $12,000 to Preston to reduce its accounts payable
On March 31, Preston reported accounts receivable at $25,000.
By April 30, accounts receivable decreased to $23,000, cash increased by $12,000, and retained earnings are expected to rise by $2,000.
The income statement will reflect a sales revenue increase of $10,000 minus $8,000 COGS, resulting in a $2,000 profit, thus contributing to retained earnings.