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.
Some sharks are fast and some sharks are slow, but the great majority cruise at very low speeds. While great whites, blues, and makos are capable of a great speed burst, most sharks swim at around 1.5 miles per hour when they're not actively chasing prey or attempting to escape from a dangerous situation. This speed falls about in line with the average human swim speed, which is between 1 and 2 miles per hour.