What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Linda is sad if and only if Jessica is sleeping. Elisabeth is driving a car or Jessica is a mechanic. For all x_3, if x_3 were a mechanic, then x_3 is sleeping. Elisabeth is not driving a car or Linda is sad.
Jessica is a mechanic or Linda is sad. If Jessica works, then Elisabeth is driving a car. If Linda were sad, then Jessica is sleeping. If Jessica sleeps, then Linda is sad.