Does anyone know what or who's price Binance uses for BTC price for the pairings?  The reason I ask is:  I saw BTC rallying on GDAX, so I sold some IOTA for BTC.  BTC went up, IOTA didn't move, and now I can't get as much IOTA back as I had in the first place.  I didn't expect they used GDAX's price, because it's always higher, but where do they get their price for BTC?