What is the difference between amendment and cancellation?

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BUS 038 : Business Computations4. You buy goods on an invoice dated October 28, with terms of 2/20, n/45. What is the last day of the discount period? 5. You buy goods at a list price of $820. If you receive a trade discount of 25% and terms are “2/15, n/30,” what amount must you pay if you pay within the discount period? 6. You receive an invoice for $18,300 with terms of 5/15, n/60. If the supplier has a policy of allowing a cash discount for partial payments and you pay $11,500 within the discount period, calculate the amount of credit you will receive for this payment. Amount credited = Amount paid Complement of cash discount rate = $11,500

Michael Jordan specially orders a 10 foot mattress from Sleepy's without a written agreement. This contract is not enforceable. 3. Explain your answer to question 2.