There is little chance that Sandra left the milk. It is highly likely that Julius is gray. We doubt that John discarded the apple. It is probable that if 'Julius is gray and John discarded the apple' then Jessica is a cat. It is unlikely that if either 'Julius is gray' or 'John discarded the apple' but not both then Brian is a rhino. There is a very good chance that if either 'Julius is gray' or 'John discarded the apple' but not both then Mary grabbed the milk.
It is probably the case that 'Jessica is a cat and Sandra left the milk'.
There is almost no chance that 'Jessica is a cat and Sandra left the milk'.
It is probably the case that 'Jessica is a cat and Sandra left the milk'.

  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
  0.1::factA.
  0.9::factB.
  0.2::factC.
  %hop1
  0.7::factX:-and(factB,factC).
  0.2::factY:-xor(factB,factC).
  0.8::factZ:-xor(factB,factC).

  %hop2
  conclusion:-and(factX,factA).

  query(conclusion).
  
'Jessica is a cat and Sandra left the milk'.