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 plays squash, then x_10 is writing a letter. There is at least one x_10 for which if x_10 writes a letter, then x_10 is a nurse. For all x_10, x_10 will drive a car or x_10 will not drink water. For all x_10, if x_10 drives a car, then x_10 is playing squash.
For all x_10, if x_10 drives a car, then x_10 is writing a letter can be inferred via the universal transitivity rule. There is at least one x_10 for which if x_10 plays squash, then x_10 is a nurse can be inferred via the existential transitivity rule. For all x_10, if x_10 drinks water, then x_10 is driving a car can be inferred via the universal rewriting rule.