I will invest all of them in altcoins, its a big risk to take as it may also bring loss for me if I choose the wrong coin, but higher reward will come only with higher risks.
Well, if I got it for free, I would probably invest it for altcoin. because so many altcoin that are rising in price today, maybe I would divide into 3 BTC to 1 altcoin. so I would have 3 coins to be stored until the price really make me a profit. well, 1 BTC might I use for trading purposes