What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_5, x_5 will play squash if and only if x_5 is a mechanic. For all x_5, if x_5 were sad, then x_5 is a mechanic. There is at least one x_5 for which x_5 will play squash.
For all x_5, if x_5 plays squash, then x_5 is a mechanic. For all x_5, if x_5 were a mechanic, then x_5 is playing squash.