What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Mary is not bored. If it is not overcast, then Elisabeth is playing squash. It is raining. It is overcast if and only if Mary is bored.
Mary is not bored and it is raining. It is raining and Mary is not bored. If it is overcast, then Mary is bored. If Mary were bored, then it is overcast. It is not overcast.