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previous - adj. existing or happening before the present time
average - adj. a number that is calculated by adding quantities together and then dividing the total by the number of quantities
background - n. the experiences, knowledge, education, etc., in a person's past
expense - n. the amount of money that is needed to pay for or buy something
superintendent - n. a person who directs or manages a place, department, organization, etc.
factor - n. something that helps produce or influence a result
maximum - adj. greatest possible in amount or degree
recruit - v. to find suitable people and get them to join a company, an organization, the armed forces, etc.
retain - v. to keep (someone) in a position, job, etc.
