What's the value for arizona when colorado and nevada are nixon, and texas is humphrey?
CREATE TABLE "politics_of_the_southwestern_states" (
  "year" text,
  "arizona" text,
  "california" text,
  "colorado" text,
  "nevada" text,
  "new_mexico" text,
  "oklahoma" text,
  "texas" text,
  "utah" text
);
SELECT "arizona" FROM "politics_of_the_southwestern_states" WHERE "colorado"='nixon' AND "nevada"='nixon' AND "texas"='humphrey';