"New Era of Mining" APP Crash

The APP operation is relatively simple. There are many kinds of mining machines on the platform. The price of different kinds of mining machines is between 800 and 6000 yuan. You can buy them at different time points or you can make an appointment through the platform in advance. "There are one day, two days, three days, five days, and seven days with the returns being 5%, 8%, 10%, 13%, and 18%, respectively." Now it's gone!