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 if and only if it is snowing. If Mary drives a car, then it is snowing. Barbara is not playing tennis. If William were bored, then Mary is driving a car. If it snows, then Mary is driving a car.
If William were bored, then it is snowing. Mary is driving a car if and only if it is snowing. It is snowing if and only if Mary is driving a car. If Barbara plays tennis, then it is snowing. If it snows, then Barbara is playing tennis. It is not snowing.