A young adult male takes advantage of the free clinic to discuss recurring symptoms with a doctor. He explains that although he feels well at the moment, he sometimes hears some sound upon exhalation, and also can experience slight chest tightness and shortness of breath on occasion. The patient states that breathing symptoms come and go but tend to worsen seasonally. Standard spirometry tests are taken before and after inhalation of an ẞ-adrenergic receptor agonist. Which of the following would be consistent with the diagnosis of asthma?