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spec: The tube would also send soil samples back to the surface and carry power to the robotic mole . At this site , Earth 's outer shell is pulling apart , allowing molten rock to rise close to the surface and feed hydrothermal springs . A major challenge to materials science is the prediction and control of microstructure . Then it sinks back to the surface and starts the loop again . For those individuals who are more optimistic about the future of a particular stock , the stock holder has every reason to believe that the stock will increase in value to its high and beyond , two alternative strategies exist to pass the stock - and future appreciation - to heirs . You think members of younger generations ought to do the same . That means giving a helping hand to those who need it and keeping the bad guys from stealing taxpayer dollars .