What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_15, if x_15 reads a book, then x_15 is sad. For all x_15, x_15 is sad or x_15 is not a musician. There is at least one x_15 for which if x_15 were sad, then x_15 is reading a book. For all x_15, if x_15 reads a book, then x_15 is a poet.
There is at least one x_15 for which if x_15 were sad, then x_15 is a poet. For all x_15, if x_15 were a musician, then x_15 is sad. There is at least one x_15 for which x_15 is sad if and only if x_15 will read a book. There is at least one x_15 for which x_15 will read a book if and only if x_15 is sad.