The electrical resistance of a thermistor is to be used to measure temperatures in the range 
to 
. The figure below shows the variation with temperature, measured in degrees Celsius, of the resistance of the thermistor.
State and explain the feature of the figure above which shows that the thermometer has a sensitivity that varies with temperature.
At one particular temperature, the resistance of the thermistor is 
. Determine this temperature, in kelvin, to an appropriate number of decimal places.
.
