Franky1 gives a computation on selling and buying. I am trying to understand and learn from videos and tips and advices from others.. Atleast now, i have an idea how to deal with it. I am trying to understand it more deeply. Anyone that can suggest free trading site where I can practice trading selling and buying for free.. I understand the computation, I want to see if the computation is equals to simulation. Thanks advance.. Feel free to share some link of free simulation of trading.. Thanks thanks..