1a. Identify the issue of law posed by the case problem.

1b. What should be the decision in the case? (i.e. the answer to the issue).

1c. The reasoning for such decision.

The parties entered into a contract to sell a weight-loss franchise and executed an "Asset Purchase Agreement" in 2004, encompassing their entire agreement. The purchase price was set at $125,000, payable at time of closing. One week later, the parties executed a "Sales Agreement Addendum," indicating an increase in the purchase price to $155,000, with $135,000 payable at closing. At the closing, a few weeks later, the buyer gave the seller $135,000.Then the disputes started. The buyer stopped payment on part of the payment made at closing and stopped making the monthly payments due for the balance remaining. Which sales price is the buyer obligated to pay and why?