What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Name the inference rule being used: For all x_10, if x_10 were rich, then x_10 is playing tennis. If it is cold, then Mary is playing tennis. It is cold or Joseph is a musician. If Joseph were a musician, then Mary is rich.
Nothing can be inferred from these premises.