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_10, if x_10 sleeps, then x_10 is a scientist. For all x_10, x_10 is rich. For all x_10, if x_10 plays squash, then x_10 is not a scientist. There is at least one x_10 for which if x_10 were rich, then x_10 is a scientist.
There is at least one x_10 for which x_10 is a scientist can be inferred via the existential modus ponens rule.