Mr. Smith has an income of $50,000. His calculations show that he owes $4,200 in taxes. He could hire a CPA for $400 to review the taxes. There is a 20% chance that the CPA could reduce taxes to $2,500, a 50% chance that taxes are reduced to $3,600, and a 30% chance that there is no reduction. Should the CPA be hired? What is the expected gain/loss in hiring the CPA?