The coefficient of real expansion of mercury is \[18\times {{10}^{-5}}/{}^\circ C.\] The thermometer bulb has a volume of \[{{10}^{-6}}{{m}^{3}}\] and the cross-section of the stem is \[0.002\text{ }c{{m}^{2}}.\] Assuming that the bulb is filled with mercury at \[0{}^\circ C\] the length of the mercury column at \[100{}^\circ C\] will be: