<span><span><span>The crust: low density silicate rock, 5-70 km thick. There are two distinct types of crust.<span><span>Continental crust is variable in thickness and composition. Thickness ranges from 5-70 km. The composition ranges from mafic to felsic.</span><span>Oceanic crust is uniform in thickness and composition. It is 5-6 km thick and is mafic in composition.</span><span>The differences in thickness and density between continental and oceanic are responsible for the existence of ocean basins due to isostatic balance as the crust floats on the more dense mantle.</span></span></span><span>The mantle: high density, ultramafic silicate rock which can flow when subjected to long duration stresses. The mantle is over 2900 km thick and makes up over 80% of the volume of the Earth. The mantle is not molten!</span></span><span>The core: iron and nickel, liquid outer region with a solid center. The core is just over half the diameter of the Earth.</span></span>
The RAF had over 50 radar stations across Britain which could find out about future attacks before the German aircraft managed to reach the coasts of Britain. This enabled them to prepare counter-attacks and their defense and ultimately rendered the German airforce completely useless. This is why Germans never managed to conquer the island.
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3. the summer is warm and mild and the winter is freezing.
The Northeast Corridor was built by several railroads between the 1830s and 1917. The route was later consolidated under two railroads: the New York, New Haven and Hartford Railroad (NYNH&H) between Boston and New York, and the Pennsylvania Railroad (PRR) between New York and Washington.
Mexico is the top producer of Lemon and limes (2.4 million tons)
