What location has a school with enrollment of 850?
CREATE TABLE "former_members" (
  "institution" text,
  "location" text,
  "founded" real,
  "type" text,
  "enrollment" real,
  "joined" text,
  "left" text,
  "nickname" text,
  "primary_conference_when_joining_the_msfa" text,
  "current_primary_conference" text
);
SELECT "location" FROM "former_members" WHERE "enrollment"=850;