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_1, x_1 will play squash. For all x_1, if x_1 were a sailor, then x_1 is working. There is at least one x_1 for which if x_1 plays squash, then x_1 is a sailor.
There is at least one x_1 for which x_1 is a sailor can be inferred via the existential modus ponens rule. There is at least one x_1 for which if x_1 plays squash, then x_1 is working can be inferred via the existential transitivity rule.