There is almost no chance that Lily is a frog. It is likely that Emily is a sheep. We doubt that Sandra got the football. It is impossible that if 'Emily is a sheep and Lily is a frog' then Brian is a lion. Chances are about even that if either 'Sandra got the football' or 'Emily is a sheep' but not both then Julius is yellow. It is probable that if either 'Emily is a sheep' or 'Lily is a frog' but not both then Mary went to the office.
It is certain that 'Sandra got the football and Lily is a frog'.
It is impossible that 'Sandra got the football and Lily is a frog'.
It is certain that 'Sandra got the football and Lily is a frog'.

  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.
  0.7::factB.
  0.2::factC.
  %hop1
  0.0::factX:-and(factB,factA).
  0.5::factY:-xor(factC,factB).
  0.7::factZ:-xor(factB,factA).

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

  query(conclusion).
  
'Sandra got the football and Lily is a frog'.