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exposure – n. the fact or condition of being affected by something or experiencing something
range – n. a sequence, series, or scale between limits
sample – n. a representative part or a single item from a larger whole or group especially when presented for inspection or shown as evidence of quality
verbal – adj. of, relating to, or consisting of words
consistent – adj. always acting or behaving in the same way
hypothesis – n. an idea or theory that is not proven but that leads to further study or discussion
participant – n. a person who is involved in an activity or event : a person who participates in an activity or event
occur – v. to come into existence
income – n. money that is earned from work, investments, business, etc.
engage – v. to take part in or cause to take part in something
