For a steel alloy it has been determined that a carburizing heat treatment of 7 hour duration will raise the carbon concentration to 0.38 wt% at a point 3.8 mm from the surface. Estimate the time (in hours) necessary to achieve the same concentration at a 6.2 mm position for an identical steel and at the same carburizing temperature.

An electric kettle is made out of stainless steel, weighs two pounds (when empty) and is equipped with a heating element that consumes 2 kw of electricity. assuming that the water and the kettle are at the same uniform temperature at any moment of time, calculate the shortest possible time to bring 2 quarts of water from room temperature to the onset of boiling