C

     There are many festivals at our school. This month is October. In October there is a sports festival. We have the volleyball game and the basketball game during(在……期间) the festival. On October 15th，there is an English festival. On that day we have an English speech contest(演讲比赛)．On October 19th，we have a school trip. We go to Beijing with the teachers. On the last day of this month，there is a music festival. On that day we can enjoy beautiful music. It's really wonderful. Next month，there is an art festival. Students often display(展示) their pictures on that day.

蚯蚓能生活在黑暗潮湿的环境中，同时它又可以疏松土壤，分解有机物增加土壤肥力，这说明（  ）

对于函数f（x），若存在x₀∈R，使f（x₀）=x₀成立，则称x₀为f（x）的一个不动点．设函数f（x）=ax²+bx+1（a＞0）．

（Ⅰ）当a=2，b=﹣2时，求f（x）的不动点；

（Ⅱ）若f（x）有两个相异的不动点x₁，x₂，

（ⅰ）当x₁＜1＜x₂时，设f（x）的对称轴为直线x=m，求证：m＞$\frac{1}{2}$；

（ⅱ）若|x₁|＜2且|x₁﹣x₂|=2，求实数b的取值范围．