— Whose ____ (knife) are in the desk? —They are Ann’s and Dick’s.
手臂上的“青筋”就是分布较浅的静脉血管.(判断对错)
已知全集U=R,集合A=x|x2-2x-3>0,B=x|2<x<4,那么集合 CUA∩B=( )