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 were a scientist, then x_10 is a server. For all x_10, if x_10 were a server, then x_10 is making tea. For all x_10, x_10 is a scientist. For all x_10, if x_10 writes a letter, then x_10 is playing tennis. For all x_10, x_10 will write a letter.
For all x_10, x_10 is a server can be inferred via the universal modus ponens rule. For all x_10, x_10 will play tennis can be inferred via the universal modus ponens rule. For all x_10, if x_10 were a scientist, then x_10 is making tea can be inferred via the universal transitivity rule. For all x_10, x_10 is a scientist and x_10 will write a letter can be inferred via the universal conjunction rule. For all x_10, x_10 will write a letter and x_10 is a scientist can be inferred via the universal conjunction rule.