What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_12, if x_12 were a server, then x_12 is playing tennis. For all x_12, x_12 will play tennis or x_12 is not a musician. For all x_12, if x_12 plays tennis, then x_12 is a server. There is at least one x_12 for which x_12 will not write a letter or x_12 is a server. For all x_12, x_12 will write a letter or x_12 is a musician.
There is at least one x_12 for which x_12 is a musician or x_12 is a server. For all x_12, if x_12 were a musician, then x_12 is playing tennis. For all x_12, x_12 is a server if and only if x_12 will play tennis. For all x_12, x_12 will play tennis if and only if x_12 is a server.