Required:

Which internal control$($s$)$ would you recommend to prevent the following situations from occurring?

$\backslash$table$[[$Situation$,],[\backslash$table$[[$a$.$ Authorization of a credit memo for a customer's account $($on receivables$)$ when the goods were never$],[$actually returned.$]],],[$b$.$ Theft of funds by the cashier, who cashed several checks and did not record their receipt.,$],[\backslash$table$[[$c$.$ Inventory stolen by receiving dock personnel. The receiving clerk claimed the inventory was sent to the$],[$warehouse$,$ but the warehouse clerk did not record properly.$]],],[\backslash$table$[[$d$.$ Writing off a customer's accounts receivable balances as uncollectible in order to conceal the theft of$],[$subsequent cash collections.$]],],[\backslash$table$[[$e$.$ Billing customers for the quantity ordered when the quantity shipped was actually less due to back$-],[$ordering of some items.$]],]]$