—I usually share them my classmates and talk about the stories each other.
A:deal with, with
B:deal with, to
C:do with, with
D:do with, for
集合A={x|1≤x<7},B={x|2<x<10},C={x|x<a},全集为实数集R.
(1)求A∪B,
(2)求(∁RA)∩B
(3)如果A∩C≠∅,求a的取值范围.