Plate tectonic is a scientific theory that says the Earth’s lithosphere is divided into several plates. The plates glide over the mantle. In early 20th century, this theoretical model builds on the concept of continental drift. It was first proposed by the scientist Alfred Wegener in 1912. After seafloor spreading was validated, the theory was accepted by the geoscientific community.
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Called "the mother of the civil rights movement," Rosa Parks invigorated the struggle for racial equality when she refused to give up her bus seat to a white man in Montgomery, Alabama. Parks' arrest on December 1, 1955 launched the Montgomery Bus Boycott by 17,000 black citizens.
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Marble is a type of rock. It is a metamorphic rock , which means rock which as changed it texture or shape or color over the time. These rocks are formed usually by uniting already existing substances on the earth. Limestone is the naturally available stone , which when undergoes metamorphosis turns into the formation of marble. Marble forms when the hot magma heats the limestone , the heat recrystallizes the calcite in the limestone changing its texture, shape etc.