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_7, if x_7 were happy, then x_7 is climbing a mountain. For all x_7, x_7 will not take a plane or x_7 is happy. For all x_7, if x_7 were a server, then x_7 is climbing a mountain. For all x_7, x_7 will take a plane or x_7 is a server. For all x_7, x_7 is a soldier.
For all x_7, x_7 is a server or x_7 is happy can be inferred via the universal resolution rule.