a，C，B，D，C，B，
fill up a vacancy
12， 1，(2n+0.8n)， 10，30，(-4a+7b，5，3
Solution (5 points)
-6，x+ 1，x=2.5，AD= 1 DE=4
This is the only place.
1. Urgent! ! ! What does the extended course include?
Olympiad, ancient poetry, ancient prose, idioms
2. What is a professional elective course?
Profe