What is the lowest wk 3 value with an n/r in wk 14, a wk 2 value of 7, and a wk 11 value greater than 18?
CREATE TABLE "ranking_movement" (
  "poll" text,
  "wk_2" real,
  "wk_3" real,
  "wk_4" real,
  "wk_5" real,
  "wk_6" real,
  "wk_7" real,
  "wk_8" real,
  "wk_9" real,
  "wk_10" real,
  "wk_11" real,
  "wk_12" real,
  "wk_13" text,
  "wk_14" text,
  "final" text
);
SELECT MIN("wk_3") FROM "ranking_movement" WHERE "wk_14"='n/r' AND "wk_2"=7 AND "wk_11">18;