Yu Xindao: “I have a friend who participated in the investigation. He told me, but due to confidentiality rules, he couldn't say much. What he revealed was also vague, but it's better than nothing.”,"Later, I'll give each of you a portable camera. Turn on the recording function and for the next four hours, you will be moving around various areas of the factory with your cameras. You can only stop recording to use the restroom. After four hours, if you haven't left the factory and your recording hasn't been interrupted for more than five minutes, you pass.",A few seconds later, he turned his head, a standard smile appearing on his round face: "Not cold."。