HURRY PLEASE Heat waves are uncomfortable for everyone, but for infants and young children, the elderly, and people who are already sick, they can be especially dangerous. Extreme heat can cause illnesses such as heat cramps, heat stroke, and even death. A 2003 heat wave in Europe caused about 50,000 deaths, and a 1995 heat wave in Chicago caused more than 600 deaths. In fact, heat waves cause more deaths in the United States every year than hurricanes, tornadoes, floods, and earthquakes combined. —“A Student’s Guide to Global Climate Change,”
US Environmental Protection Agency

Which word does the author use in the first sentence to present heat waves as a problem?

What evidence does the author include to support the idea that heat waves are a problem?