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capsule - n. a small part of the spacecraft where people live and work
item - n. a separate part or thing
shield - n. something that defends or protects something
canister - n. a metal case that contain gas, chemical or fuel
challenge - n. a difficult task or problem
schedule - n. a plan of the times when something will be done
precedence - n. a condition of being more important than something else
exceed - v. to be greater or more than something
faulty - adj. having a mistake
valve - n. a mechanical device that controls the flow of liquid, gas, etc. by opening and closing
