A 55-year-old man has been recently hospitalized for abdominal pain due to gallstone pancreatitis. During his hospitalization, he has an abdominal CT scan that shows an incidental finding of right adrenal mass 2x1 cm. He has T2DM and dyslipidemia. His current medications are atorvastatin and metformin. On examination, HR 80/min, and BP 138/80 mmHg. His investigations show normal renal function and HbA1c is 7.1% Which of the following Laboratory tests should be done to evaluate his adrenal mass?