xShadow zone : The shadow zone is the area of the earth from angular distances of 104 to 140 degrees from a given earthquake that does not receive any direct P waves. The shadow zone results from S waves being stopped entirely by the liquid core and P waves being b
Air pollution can get high in the atmosphere – high above most of the clouds you see in the sky. Scientists are finding air pollution like black carbon, sulfur dioxide, and nitrogen oxides more than 2...Read more