已知A={x|x2-3x+2≤0},B={x|x2-(a+1)x+a≤0}. (1)若AB,求a的取值范围; (2)若BA,求a的取值范围; (3)若A∩B为仅含有一个元素的集合,求a的值. 答案:解:A={x|1≤x≤2},B={x|(x-1)(x-a)≤0}, (1)若AB(图甲),应有a>2. (2)若BA(图乙),必有1≤a≤2. (3)若A∩B为仅含一个元素的集合(图丙),必有a≤1. Not only he but also I ___ able to drive a car.A. am B. isC. are D. was