题目

函数y=的值域为 .  答案：{y|y=1或y≥} 解析因为当x≤-1时,y=; 当x>-1时,y=1, 所以值域为{y|y=1或y≥}.— Tom's been sent to the USA for further study. What about his twin sister?— _____.How lucky they are!   [     ]A. So has she    B. She is too     C. So is she        D. So she has