What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? There is at least one x_5 for which if x_5 were a mechanic, then x_5 is an electrician. For all x_5, if x_5 were an electrician, then x_5 is writing a letter. For all x_5, if x_5 writes a letter, then x_5 is an electrician.
There is at least one x_5 for which if x_5 were a mechanic, then x_5 is writing a letter. For all x_5, x_5 is an electrician if and only if x_5 will write a letter. For all x_5, x_5 will write a letter if and only if x_5 is an electrician.