What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Barbara is playing tennis or it is not late. If Michael were sad, then Barbara is playing tennis. If Susan were an astronaut, then Michael is sad. Karen is a musician or it is late. If Karen were a musician, then Susan is an astronaut.
If Susan were an astronaut, then Barbara is playing tennis. If Karen were a musician, then Michael is sad. If it is late, then Barbara is playing tennis.