There is almost no chance that Jeff moved to the office. There is almost no chance that Emily is a sheep. Chances are slight that Julius is white. There is a very good chance that if 'Jeff moved to the office' or 'Julius is white' or both then Brian is a frog. We doubt that if either 'Jeff moved to the office' or 'Julius is white' but not both then Greg is a frog. Chances are about even that if either 'Emily is a sheep' or 'Julius is white' but not both then Mary grabbed the apple.
Chances are about even that 'Jeff moved to the office and Julius is white'.
It is impossible that 'Jeff moved to the office and Julius is white'.
Chances are about even that 'Jeff moved to the office and Julius is white'.

  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.
  0.02::factB.
  0.1::factC.
  %hop1
  0.8::factX:-or(factA,factC).
  0.2::factY:-xor(factA,factC).
  0.5::factZ:-xor(factB,factC).

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

  query(conclusion).
  
'Jeff moved to the office and Julius is white'.