What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Joseph is a mechanic if and only if it is cold. For all x_11, x_11 will play a game or x_11 will sleep. If Mary sleeps, then Joseph is a mechanic. It is not cold. Mary is not playing a game or James is climbing a mountain.
If Joseph were a mechanic, then it is cold. If it is cold, then Joseph is a mechanic. Joseph is not a mechanic.