for better research go to under NOAA - Climate.gov
This is a short paraphrased summary of the article about ice cores in that website.
Answer: Researchers in labs may melt or crush bits of the ice core a little at a time, each deeper layer shows the time in the Earth's climate history. Tiny pieces of pollution, metals, radoiactive fallout, pebbles, sea salt, volcanic ash and even air bubbles all present important information that researchers can look for to track changes in the atmosphere's composition and temperature.
Answer:
The United States and Mexico depend on each other more than ever for our economic well-being and competitiveness. We will sink or swim together in the global economy.
Explanation:
In areas where the plates come together, sometimes volcanoes will form. Volcanoes can also form in the middle of a plate, where magma rises upward until it erupts on the seafloor, at what is called a “hot spot.” The Hawaiian Islands were formed by such a hot spot occurring in the middle of the Pacific Plate.
