Any help on any question would be immensely appreciated

Task 1 a) List three implications of effective doubtful debt identification policy. (3 marks) b) List three reasons for which discrepancies between monies recorded and monies paid may occur. (3 marks) c) When you are filing documents, what factors should be considered when deciding the filing order? (3 marks) d) To identify and describe the key features of accounting systems, we must maintain accurate record keeping and reconciliations. What controls should be in place to maintain accurate records for recording source documents into the subsidiary ledgers