What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_10, if x_10 were a janitor, then x_10 is taking a plane. For all x_10, x_10 will not climb a mountain. For all x_10, x_10 will climb a mountain or x_10 will write a letter. For all x_10, x_10 will read a book or x_10 is a janitor. For all x_10, x_10 will take a plane or x_10 will not read a book.
For all x_10, x_10 will write a letter. For all x_10, if x_10 reads a book, then x_10 is taking a plane.