Teacher:In this task, you are given a paragraph, event and an entity. The event is part of the given paragraph and it changes the state of the entity. Your task is to classify the state of the entity into three classes: 1) not exist, 2) unknown location and 3) known location. "not exist" means the entity doesn't exist in that state anymore. "unknown location" means the entity exists in that state but location is unknown. "known location" means the entity exists and location is known. 
Teacher: Now, understand the problem? Solve this instance:  "process paragraph : : You inhale air through your nose and mouth. The air travels down into your lungs. Oxygen from the air goes into your bloodstream. Oxygen circulates throughout the body due to the heart's pumping. Carbon dioxide travels from the blood into the lungs. Carbon dioxide travels from the lungs up the windpipe. Carbon dioxide is exhaled. ", "event : The air travels down into your lungs.", "entity : air" 
Student:
 known location 