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variant - n. something that is different in some way from others of the same kind
income –n. money that is earned from work, investments and business; used to describe the average amount of money people make is a certain place
booster (shot) –n. an extra amount of a vaccine that is injected into a person or animal that improves or extends protection against a targeted disease
expose - v. to cause something to be affected by a virus or something that could be harmful
emphasize - v. to give special attention to something
critical - adj. extremely important
peak - adj. filled with the most activity
