Mike is the Controller at Combine Supply Company. Combine Supply has an investment account with a large brokerage. Mike is authorized to call the broker and initiate trades on behalf of the company. Mike's son goes to VEU $($Very Expensive University$).$ While Mike has a CD with the money for this year's tuition, VEU changed the tuition due date such that the tuition came due $30$ days before Mike's CD matured. Mike would lose a large amount of interest ifhe cashed in the CD early, and a loan from the bank was not possible because Mike is already over extended.Interest on a credit card advance would be $28\%.$Page $4$:$4$Page $5$:$5$Page $6$:kMike authorized the broker to sell one of the company's investments and send the check to his attention at the company. Mike paid the tuition and $30$ days later, when the CD came due Mike repurchased the investment with the broker. In fact, the stock had dropped $$3$ and Mike made a profit of $5900.($a$)$ What internal control weakness allowed this situation to occur?$($b$)$ What is one specific internal control that Combine Supply should put in place to prevent or detect this situation in the future?$($c$)$ What is one test of control audit procedure that the auditors should use?$($d$)$ What is one substantive test that the auditors could use to detect the situation?