What can be inferred from the following premises in a single inference step (ignoring inferences that add new predicates or constants)? Karen is sad or it is overcast. If it is overcast, then David is drinking water. If Thomas drives a car, then Karen is an astronaut. If Karen were sad, then David is drinking water. If David drinks water, then Thomas is driving a car.
If it is overcast, then Thomas is driving a car. If Karen were sad, then Thomas is driving a car. If David drinks water, then Karen is an astronaut. David is drinking water.