Reset Button. Most boilers have safety devices built in, so if these are tripped a simple reset may get your whole system working. The reset button is normally on the front of the boiler. Sometimes it's a dial that needs resetting to zero and turned back on.
A typical diffusion constant for a medium-sized molecule in water is about . If we want the smell to travel a quarter mile, or a little less than , we get a speed of. This speed is fantastically slow, and says that it would take ten million years for blood to diffuse out to a shark a quarter mile away.
Great whites can detect one drop of blood in 25 gal (100 L) of water and can sense even tiny amounts of blood in the water up to 3 mi (5 km) away. Size relative to a bus: The legendary great white shark is far more fearsome in our imaginations than in reality.