Required information [The following information applies to the questions displayed below.] Fraud Investigators Incorporated operates a fraud detection service. a. On March 31,10 customers were billed for detection services totaling $35,000. b. On October 31, a customer balance of $2,000 from a prior year was determined to be uncollectible and was written off. c. On December 15 , a customer pald an old balance of $800, which had been written off in a prior year. d. On December 31, $600 of bad debts were estimated and recorded for the year