Read the following text to answer questions number 17 to 20.

A storm is a disturbance of the ordinary conditions of the atmosphere accompanied by wind, rain, snow, sleet, hail (frozen rain), or thunder and lighting. Types of storms include the extra tropical cyclone, the common, large-scale storm of temperate latitudes; the tropical cyclone, or hurricane, which is somewhat smaller in area than the former and accompanied by high winds and heavy rains; the tornado, or “twister,” a small but intense storm with very high winds, usually of limited duration; and the thunderstorm, local in nature and accompanied by brief but heavy rain showers and often by hail. The term storm is also applied to blizzard, sandstorms, and dust storms, in which high wind is the dominant meteorological element.

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