题目

 集合A＝{(x，y)|y＝a}，集合B＝{(x，y)|y＝bx＋1，b>0，b≠1}，若集合A∩B只有一个子集，则实数a的取值范围是( ) A．(－∞，1)                            B．(－∞，1] C．(1，＋∞)                            D．R 答案：B若A∩B只有一个子集，则这个子集为空集Ø，即A∩B＝Ø，作出y＝a和y＝bx＋1(b>0且b≠1)的图象．由图可知a≤1时，y＝a与y＝bx＋1无公共点．A) 根据句意和汉语提示写出单词,完成句子。【1】________ (没有)your suggestions, I couldn’t complete the project perfectly.【2】Don’t ________ (承诺) her anything if you don’t want to get into trouble.【3】Tony’s grandma still looks very healthy in her________ ( 九十多岁).【4】I have been to Beijing. I think the Great Wall is worth________ (参观).【5】Tom is________ (着迷的) about football. He plays football even when it rains.