Adam Purchased Stock in 2006 for $100,000

Adam purchased stock in 2006 for $100,000.He is considering selling it in 2015.It is currently worth $2,100,000 so he would realize a $2,000,000 gain.Adam is in the top tax bracket.Determine the taxes due under the following independent situations (ignore any additional Medicare taxes on investment income):
(a)Adam sells the stock,and no special circumstances apply.
(b)The stock is qualified small business corporation stock.
(c)The stock is qualified small business corporation stock.Within 60 days Adam invests $2,500,000 in new qualifying small business corporation stock.
(d)The stock is qualified small business corporation stock.Within 60 days Adam invests $2,000,000 in new qualifying small business corporation stock.