If an unforeseen event occurs after a contract has been made that makes one of the parties performance under the contract prohibitively more experience than was contemplated when the contract was made: the party whose performance is now more expensive still has to perform the obligations under the contract or the party's obligation to perform under the contract can be cancelled under the doctrine of commercial impracticability or the parties to the contract will have to renegotiate the terms of the contract or the contract is automatically breached