CRE Multi-tenant Office Investment. (Purchase Price = 30,000,000; Acquisition Cost = 100,000; Land Value = 6,000,000; Land Improvements = 1,000,000; 7-yr Property 4,000,000; Bullet Loan 21,000,000; Interest Rate = 5%; Points = 2; Term = 7 years; NOI Year 3 = 800,000; CAPEX Year 3 = 75,000; Net Sale Price Year 7 = 35,000,000; Sum of Depreciation = $8,800,000; Adjusted Basis = 22,000,000; Capital Gain Tax Rate = 20%) What is your Capital Gain Tax?

Answer is 840,000. I need the explanation on how to get this number and from where your numbers come from.