Highlights. 1  Acute myocardial infarction is the medical name for a heart attack. 2  A number of different factors may increase your risk for a heart attack, including high blood pressure, high cholesterol, and diabetes.  Call 911 immediately if you believe you or someone you know may have had a heart attack.
The blue color of the sky is due to Rayleigh scattering. As light moves through the atmosphere, most of the longer wavelengths pass straight through. Little of the red, orange and yellow light is affected by the air. However, much of the shorter wavelength light is absorbed by the gas molecules.
The Sky Is Gray Themes. This Study Guide consists of approximately 53 pages of chapter summaries, quotes, character analysis, themes, and more - everything you need to sharpen your knowledge of The Sky Is Gray.