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EntertainmentThe reason for manhole covers is usually round
The manhole cover in a round shape allows easy installation, transportation as well as preventing risk of leakage.Why are manhole covers designed circularly?
With a circular structure, the top-down force will be dispersed evenly across the surface to help the manhole cover be affected.
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Why do people who die on Mount Everest have to stay there forever?
Why is hypertension getting younger?
Why do many scientists believe that ants are the most perfectly evolved creatures on Earth?
The reason why seats at many train stations in Japan do not face the tracks
A New Ocean Appears on Earth in an Unbelievable Place
The mystery of the 'Buddha's tears' of the giant Leshan Buddha statue: Scientific phenomenon or legend?
Earth swallows itself and 'chokes' in the Pacific Ocean?
Nano-sized water bubbles filmed forming out of air
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