Whenever Dylan walks into his room, his roommate loudly blows an air horn, which startles Dylan. Dylan doesn't think this is fun
ny, and after several such episodes, he tenses up and opens the door more slowly and carefully. In this practical joke, Dylan's reflex of tensing up whenever he opens the door is the ________.
providing energy to an atom can allow the electron in its non valence shell to obtain energy and move to a higher energy orbital and act as a valence electron.
