What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_12, x_12 is fast if and only if x_12 is rich. Charles is not a musician. Charles is a musician if and only if William is a nurse. William is a nurse or Sarah is not fast.
If Sarah were fast, then William is a nurse. If Charles were a musician, then William is a nurse. If William were a nurse, then Charles is a musician. William is not a nurse. For all x_12, if x_12 were fast, then x_12 is rich. For all x_12, if x_12 were rich, then x_12 is fast.