Consider the following premises. If Susan were a nurse, then Jessica is a janitor. Karen is taking a plane or Susan is a nurse. If Jessica were a janitor, then Patricia is an office clerk. Elisabeth is sleeping. If Karen takes a plane, then Patricia is an office clerk. Can we infer the following from them? Patricia is not an office clerk.
 From the fact that if Susan were a nurse, then Jessica is a janitor, and that if Jessica were a janitor, then Patricia is an office clerk we can infer that if Susan were a nurse, then Patricia is an office clerk. Finally, from the fact that if Karen takes a plane, then Patricia is an office clerk, that if Susan were a nurse, then Patricia is an office clerk, and that Karen is taking a plane or Susan is a nurse we can infer that Patricia is an office clerk, which contradicts that Patricia is not an office clerk. Therefore, the answer is no.