Problem 4 (11 marks): The accounts receivable department has documented the following defects over a 30-day period: Category Invoice amount does not agree with the cheque Frequency 108 amount Invoice not on record (not found) 24 No formal invoice issued 18 Cheque (payment) not received on time 30 Cheque not signed 8 Invoice number and invoice referenced do not agree 12 What technique/tool would you use and why? Using the tool you selected, show what conclusions you might suggest.