1. To go down we'd (almost certainly) need all three of Hull, Sunderland, and Leicester to over-take us.
2. Sunderland have to play Arsenal and Chelsea.
3. Hull have yet to play Liverpool, Arsenal, Spurs, and Man Utd.
4. Sunderland and Leicester have to play each other. Obviously only one of them can get three points from that match.
We'll be fine.