There is a better than even chance that Mary left the football. It is improbable that Greg is yellow. It is almost certain that Julius is white. Chances are slight that if either 'Julius is white' or 'Greg is yellow' but not both then Fred put down the apple. It is unlikely that if 'Mary left the football and Julius is white' then Jessica is a sheep. There is little chance that if 'Mary left the football' or 'Greg is yellow' or both then Brian is yellow.
It is impossible that 'Fred put down the apple' or 'Julius is white' or both.
It is almost certain that 'Fred put down the apple' or 'Julius is white' or both.
It is impossible that 'Fred put down the apple' or 'Julius is white' 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
  0.6::factA.
  0.1::factB.
  0.95::factC.
  %hop1
  0.1::factX:-xor(factC,factB).
  0.2::factY:-and(factA,factC).
  0.1::factZ:-or(factA,factB).

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

  query(conclusion).
  
'Fred put down the apple' or 'Julius is white' or both.