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marine – adj. of or relating to the sea or the plants and animals that live in the sea
introduce – v. to put in
communicate – v. to give information about (something) to someone by speaking, writing, moving your hands, etc.
species – n. biology : a group of animals or plants that are similar and can produce young animals or plants : a group of related animals or plants that is smaller than a genus
volume – n. the degree of loudness or the intensity of a sound
frequency – n. the number of waves of sound or energy that pass by a point every second
stress – n. a state of mental tension and worry caused by problems in your life, work, etc.
essential – adj. extremely important or necessary
monitor – v. to watch, keep track of, or check usually for a special purpose
