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expose - v. to leave (something) without covering or protection
concentration - n. the amount of a component in a given area or volume
remote - adj. far away
asthmatic - adj. relating to asthma, a lung disorder that causes periods of wheezing, coughing, and difficulty with breathing
button - n. a small part of a machine that you push to make the machine work
function - n. the special purpose or activity for which a thing exists or is used
source - n. the cause of something; someone or something that provides what is wanted or needed
ton - n. a measure of weight equal either to 2000 pounds (about 907 kilograms) (short ton) or 2240 pounds (about 1016 kilograms; long ton ) with the short ton being more frequently used in the United States and Canada
irritate - v. to make (someone) impatient, angry, or annoyed
symptom - n. a change in the body or mind which indicates that a disease is present
