What is the average Against, when Status is "2007 Rugby World Cup", and when Opposing Teams is "U.S.A."?
CREATE TABLE "2007" (
  "opposing_teams" text,
  "against" real,
  "date" text,
  "venue" text,
  "status" text
);
SELECT AVG("against") FROM "2007" WHERE "status"='2007 rugby world cup' AND "opposing_teams"='u.s.a.';