Confirmation requests to debtors are one of the audit procedures to obtain sufficient appropriate evidence as to trade accounts receivable. Required: a. If there is no response to a positive confirmation, suggest THREE auditing steps that you should perform. (6 marks) b. If there is no response to a negative confirmation, suggest the implications. (3 marks) c. Suggest THREE necessary information that your client can provide to help with the preparation of confirmation requests to debtors. (3 marks) d. In addition to sending confirmation requests, your audit junior is seeking your advice on how to evaluate whether trade accounts receivable is fairly valued at the year-end date. Briefly describe THREE methods. (6 marks)