1. In the scope of investigation, the key middle schools in the experimental class enrolled students, selected school papers, and investigated all mathematics knowledge in junior high schools, with a wide scope of investigation.

2. As for the questioner, the Mathematics for Enrollment and School Choice of Key Middle Schools in the experimental class was written by the famous saint education experts in the school as the subject. Therefore, it is difficult for key middle schools in experimental classes to recruit students and choose school papers.