What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_14, if x_14 were a taxi driver, then x_14 is playing squash. For all x_14, if x_14 plays squash, then x_14 is sad. For all x_14, if x_14 were sad, then x_14 is listening to a song. For all x_14, x_14 will not listen to a song. Karen is cooking if and only if Susan is a taxi driver.
If Karen cooks, then Susan is a taxi driver. If Susan were a taxi driver, then Karen is cooking. For all x_14, x_14 is not sad. For all x_14, if x_14 were a taxi driver, then x_14 is sad. For all x_14, if x_14 plays squash, then x_14 is listening to a song.