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commercial - adj. related to or used in the buying and selling of goods and services
executive - n. a person who manages or directs other people in a company or organization
frequency - n. the number of times that something (such as a sound wave or radio wave) is repeated in a period of time (such as a second)
mobile - adj. able to move from one place to another
solar - n. produced by or using the sun's light or heat
