I am an American boy. 1name is Paul. I am 12. I2two friends, Sally and Mona. They're3. We play sports4 We play soccer, basketball, volleyball and5 Sally6a sports collection（收藏）.7has seven soccer balls,8basketball, four volleyballs, and six tennis rackets. We often(经常)9volleyball on TV. What sports10you often play?

①改革税制增加社会各阶层收入       ②逐步增加社会公共物品的供给

③提高初次分配中劳动报酬比重          ④不断加强社会保障体系的建设

函数y=x²+bx+c与y=x的图像如图所示，有以下结论：

①b²﹣4c＞0；②3b+c+6=0；③当1＜x＜3时，x²+（b﹣1）x+c＜0；

④ $\sqrt{b^2+c^2}=3\sqrt{2}$ ，其中正确的有____