Mathematical Experiment 7
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Construct this structure by joining four surfaces each of which is a part of the hemisphere: 
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Construct three mutually tangential cylinders of the same
size situated like this:

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Arrange three identical mutually tangential cones like this: 
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Arrange four identical mutually tangential halfcones like this: 
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Arrange eight identical halfcones each tangent to the other
three like this: ¡@ 
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Construct the solid bounded by the parabolic cylinder z = 4  y^{2} and the elliptic paraboloid z = x^{2} + 3y^{2}. 
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