What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? For all x_10, if x_10 takes a plane, then x_10 is working. For all x_10, x_10 is sad. For all x_10, x_10 will take a plane. For all x_10, if x_10 were sad, then x_10 is writing a letter. For all x_10, if x_10 works, then x_10 is a scientist.
For all x_10, x_10 will work. For all x_10, x_10 will write a letter. For all x_10, if x_10 takes a plane, then x_10 is a scientist. For all x_10, x_10 is sad and x_10 will take a plane. For all x_10, x_10 will take a plane and x_10 is sad.