It is probable that Daniel grabbed the milk. There is almost no chance that Mary dropped the apple. It is probably the case that Julius is gray. It is probably the case that if 'Mary dropped the apple and Julius is gray' then Greg is a lion. There is a very good chance that if 'Julius is gray' or 'Mary dropped the apple' or both then Brian is gray. It is highly likely that if 'Daniel grabbed the milk' or 'Mary dropped the apple' or both then John went to the kitchen.
There is a better than even chance that 'Brian is gray' or 'Mary dropped the apple' or both.
There is a better than even chance that 'Brian is gray' or 'Mary dropped the apple' or both.
There is almost no chance that 'Brian is gray' or 'Mary dropped the apple' 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
  0.7::factA.
  0.02::factB.
  0.7::factC.
  %hop1
  0.7::factX:-and(factB,factC).
  0.8::factY:-or(factC,factB).
  0.9::factZ:-or(factA,factB).

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

  query(conclusion).
  
'Brian is gray' or 'Mary dropped the apple' or both.