how well the flu vaccine is matched to flu viruses that are causing illness. Over a period of 31 seasons between 1976 and 2007, estimates of flu-associated deaths in the United States range from a low of about 3,000 to a high of about 49,000 people.
metamorphic rocks form from heat and pressure changing the original or parent rock into a completely new rock the parent rock can be either sedimentary igneous or even another metamorphic rock the word metamorphic comes from greek and means to change form the diagram above shows you how the rocks on earth have been changed continually over time from one rock type to another
Metamorphic rocks form deep in the earth where high temperature, great pressure, and chemical reactions cause one type of rock to change into another type of rock.Metamorphic â¦ rocks begin to form at 12-16 kilometers beneath the earth's surface.etamorphic rocks are formed from igneous, sedimentary, or other metamorphic rocks.