Which Debuff Effects Stack/Interact?

There are five debuffs that exist in TF2 (that I can think of at the moment, that are player-caused and not Fear). They are:

Now, say someone was unlucky enough to have all four of these effects on them at the same time. Which of them would stack/interact with one another?

To be more specific:

Would Fire or Bleeding do more damage to a Marked-For-Death or Jarate'd individual?
Would a Milked individual provide constant health to the player who caused them to burn/bleed?
Would the same Milked person provide more health while under the effects of Jarate or a Mark For death?
Do these stacking effects change depending on the item that inflicted them? (Self-inflicted Marked-For-Death of Heavy/Soldier, vs. the Scout's Fan of War, or being hit by a Scout's Guillotine vs. a scout hitting himself with the Boston Basher).

Solution 1:

All the debuffs stack except for Marked for Death and Jarate (as they both provide mini-crits). Now for your bullet-point questions:

Mini-crit fire (both Jarate and Marked for Death) deals one more point of fire damage (4 if you're not using the Degreaser, 3 if you are).
Fire and bleed damage would indeed heal if their target is currently Milked.
As recovery off of Milked is based off of damage dealt, the health recovered off mini-crit damage would increase (you would recover 2 health rather than 1 as your fire/bleed damage does 4 damage rather than 3).
Debuffs do not differ in magnitude depending on the weapon that applied them, so these stacking effects would not change.

P.S. Credit to Powerlord for providing assistance and knowledge