It is impossible that Mary is in the park. It is almost certain that Julius is a swan. We doubt that John discarded the milk. There is little chance that if Mary is in the park, or Julius is a swan, then Bill dropped the milk. It is probable that if Julius is a swan, or Mary is in the park, then Greg is green. There is little chance that if either John discarded the milk, or Julius is a swan, then Brian is green.
It is impossible that brian is green, and Mary is in the park.
It is impossible that brian is green, and Mary is in the park.
Chances are about even that brian is green, and Mary is in the park.
Brian is green, and Mary is in the park.