A.M∩N                B.M∪N            C.(M∩N)       D.(M∪N)

A.{1，2}              B.{3，4}           C.{1}           D.{-2，-1，0，1，2}

A.{x|-2＜x＜1}                               B.{x|-3＜x＜3}

C.{x|1＜x＜3}                                D.{x|x＜-3或x＞-1}

A.|x|x＞1}                                      B.{x|x≥1}

C.{x|x＞1或x=0}                            D.{x|x≥1或x=0}

A.{x|x＜3}                                  B.{x|x＞3}

C.{x|x＞-3}                                 D.{x|-3＜x＜3}