calculate- v. to get a general idea about the value of something
tornado- n. a violent and destructive storm in which powerful winds move around a central point
county- n. an area of a state or country that is larger than a city and has its own government to deal with local matters
hazard- n. a source of danger
vulnerability- n. the state of being open to attack, harm or damage
infrequent- adj. an act that does not happen often