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Heat and Health
Extremely hot weather is common in many parts of the world. Although hot weather just makes most people hot, it can cause medical problems--and death.
Health experts say that since the year 1900, extremely hot weather has killed more people in the United States than any other natural event. One year--the unusually hot summer of 1980--heat caused about 1,700 deaths in the United States. In 1995, more than 600 people died in a similar heat wave in one city--Chicago.
To measure extreme heat, government weather experts have developed the Mean Heat Index. It measures the average of how hot it is felt all day on an extremely hot day. Experts say it is the total heat of a hot day or several hot days that can affect health. Several hot days are considered a heat wave. Experts say heat waves often become deadly when the nighttime temperature does not drop much from the highest daytime temperature.
The most common m
A. The average temperature of an extremely hot day.
B. The highest temperature of an extremely hot day.
C. The lowest temperature of an extremely hot day.
D. The nighttime temperature of an extremely hot day.