There is almost no chance that Yann is thirsty. It is improbable that Mary grabbed the apple. Chances are slight that Greg is yellow. It is highly likely that if either 'Greg is yellow' or 'Mary grabbed the apple' but not both then Emily is a mouse. It is almost certain that if 'Yann is thirsty and Mary grabbed the apple' then Julius is green. It is almost certain that if 'Greg is yellow' or 'Yann is thirsty' or both then Jeff discarded the milk.
There is little chance that 'Julius is green' or 'Greg is yellow' or both.
There is little chance that 'Julius is green' or 'Greg is yellow' or both.
There is a better than even chance that 'Julius is green' or 'Greg is yellow' or both.

  and(A,B) :- A,B.
  or(A,B) :- A;B.
  nand(A,B) :- not(and(A,B)).
  nor(A,B) :- not(or(A,B)).
  xor(A,B) :- or(A,B), nand(A,B).

  %hop0
  0.02::factA.
  0.1::factB.
  0.1::factC.
  %hop1
  0.9::factX:-xor(factC,factB).
  0.95::factY:-and(factA,factB).
  0.95::factZ:-or(factC,factA).

  %hop2
  conclusion:-or(factY,factC).

  query(conclusion).
  
'Julius is green' or 'Greg is yellow' or both.