Answer:
TRUE
Explanation:
The scenario is portraying the modification to a contract
A modification of contract is any change, in part or whole, occurring to a legally binding agreement between two or more parties. Any contract can be modified before or after signing the agreement, but all parties must agree to the changes. If any party doesn't agree to the modification, the changes are invalid.
Hence, it is true that the Thrashers would be obligated to pay the additional sum because the original agreement already obligated Carl to complete the deck for $7,000.