Look at the picture. Who is the girl? She is my friend. Her name is Alice Black. She is an English girl.

       Alice has a big family. Her grandparents have two daughters and one son — her father. Alice lives with her grandparents, parents, two brothers and one sister. Alice has two dogs — Bobby and Tony. Bobby is black and Tony is white. Alice likes them very much. Alice is a middle school student. She has a good friend at school. Her name is Helen. They are cousins, too.

已知方程：（m²﹣1）x²+（m+1）x+1=0，求：

（1）当m为何值时原方程为一元二次方程．

（2）当m为何值时原为一元一次方程．

表一：

机器人中吸尘电机的吸入功率是衡量其优劣的重要参数，测得某吸尘电机的吸入功率与真空度、风量间的对应关系如表二。真空度指主机内部气压与外界的气压差。风量指单位时间内通过吸尘电机排出的空气体积。吸尘电机吸入功率与输入功率的比值叫做效率。

表二：