$BTC The 5000-point up and down wash of the big cake is indeed strong, but the support of 855-845 is still relatively strong. It is not only the Fibonacci 618-50 range, but also the area where the lower edge of the oscillation box is located. It has also been verified by the K-line as a support. It can be used as a reference for trading. However, once this position is broken, it will most likely start a wave of correction!