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_11, x_11 will play tennis or x_11 will not take a plane. For all x_11, x_11 will play tennis if and only if x_11 is a mechanic. There is at least one x_11 for which x_11 will not drive a car or x_11 will take a plane. For all x_11, x_11 will drive a car or x_11 is a mechanic.
There is at least one x_11 for which x_11 is a mechanic or x_11 will take a plane can be inferred via the existential resolution rule. For all x_11, if x_11 takes a plane, then x_11 is playing tennis can be inferred via the universal rewriting rule. For all x_11, if x_11 plays tennis, then x_11 is a mechanic can be inferred via the universal biconditional elimination rule. For all x_11, if x_11 were a mechanic, then x_11 is playing tennis can be inferred via the universal biconditional elimination rule.