Please i need a full answer for all questions with explanation. Thanks in advance

Scenario: Don, an elderly man, lives with his nephew Evan. Don is entirely dependent on Evan for support and his care. Evan advised Don to "invest" in Evan's new consulting business or Evan will no longer support him. Don liquidated his other investments and a trust fund and signed a contract with Evan giving all his investments and trust funds to Evan for Evan's new business.

Later, Don had doubts about Evan's new consulting business and wanted out of the contract.

Can Don set aside the contract with Evan, or is it valid and enforceable? Why or why not? Specifically, what defenses can Don use to avoid the contract? Specifically, what defenses can Don use to avoid the contract? Identify, define, and provide the elements of the defenses and how they would apply?