are you kidding me? you ask for advise in coin? go bet that 4k you may take more than double and you may lose all of them.
trading will not return you double for only two weeks, its a medium and long term investment unless the price will go the same way like in the end of 2017
It is good to dream a little wild my friend. To think about the impossible and chase ones imaginations because that way a person can grow a lot and someday, even if he fails to do what he aimed for, he will be far above others who did not even bothered to take first step in this direction. Besides, nothing is really impossible. Trading with the right asset at right time can return big amounts.