How many cover dates does the story "Devastation Derby! (part 1)" have?
CREATE TABLE "table1_18305523_2" (
  "num" real,
  "cover_date" text,
  "story_title" text,
  "writer_s" text,
  "artist_s" text,
  "letterer_s" text,
  "colourist_s" text,
  "editor_s" text,
  "comments" text
);
SELECT COUNT("cover_date") FROM "table1_18305523_2" WHERE "story_title"='DEVASTATION DERBY! (Part 1)';