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_14, if x_14 were a musician, then x_14 is climbing a mountain. For all x_14, if x_14 works, then x_14 is not climbing a mountain. For all x_14, if x_14 writes a letter, then x_14 is climbing a mountain. For all x_14, x_14 will work or x_14 is not an astronaut. There is at least one x_14 for which if x_14 works, then x_14 is an astronaut. For all x_14, x_14 will write a letter or x_14 is a musician.
For all x_14, if x_14 were an astronaut, then x_14 is working can be inferred via the universal rewriting rule. For all x_14, x_14 will climb a mountain can be inferred via the universal disjunction elimination rule.