3. An old Walmart courtesy policy stated, "When the discount price for any merchandise was not correctly given to the customer at the check-out counter due to the computer error, (1) you will have that only one item for free if its correct unit price is under $3.90; or (2) you are entitled to a $3.90 cash refund if your total purchase on the same transaction of one or multiple merchandise items exceeds $3.00". One day, the price for Great Value large eggs dropped from $1.28 per dozen down to $1.00 per dozen. I picked up four (4) dozens of them, and went through the check-out counter to pay for. No surprise, the computer checked them out still as the old price as $1.28 a dozen. The manager told me that, with her understanding on the policy, I only need to pay the corrected discount price plus tax on three dozens of eggs, and entitled to take the fourth dozen home for free. But, I told her that her statement was incorrect that, according to my understanding of the policy, I deserve the discounted unit price on each dozen of eggs, of course including the sales tax; but plus, I deserve a $3.00 cash refund after the correct transaction is carried out. Finally, I made the manager fully understand her own policy correctly. (1) How much money should I pay correctly for the four dozens of eggs according to the policy under this circumstance (Must show your work for credits)? (2) How much money would I be incorrectly charged for the four dozens of eggs according to the policy understood incorrectly the manager (Must show your work for credits)