Steps, just a question has been answered. The price of the back cover changes in real time like the stock, and now it is 2. 445 doesn't mean it will be the same price in the future. You've seen the stock exchange, right? The price on the big screen of the stock exchange is changing all the time. Your principle is to buy as low as possible and sell as high as possible to earn the difference.

As I said just now, the trading rate on one side is 1. Between 5 and 3.