-- Database schema
| workshop : Workshop_ID [ INT ] primary_key , Date [ TEXT ] , Venue [ TEXT ] , Name [ TEXT ] | submission : Submission_ID [ INT ] primary_key , Scores [ INT ] , Author [ TEXT ] , College [ TEXT ] | Acceptance : Submission_ID [ INT ] primary_key Acceptance.Submission_ID = submission.Submission_ID , Workshop_ID [ INT ] Acceptance.Workshop_ID = workshop.Workshop_ID , Result [ TEXT ] |
-- -- Show the colleges that have both authors with submission score larger than 90 and authors with submission score smaller than 80.

SELECT College FROM submission WHERE Scores  >  90 INTERSECT SELECT College FROM submission WHERE Scores  <  80;