Almost the entire volume of mercury in a thermometer is contained in the bulb. The remainder extends up into a capillary tube. Suppose that the bulb has a volume of 1.21 cm3. Find the inner radius of the capillary tube if the level of the mercury rises 1.67 cm per Celsius degree increase in temperature. Thermometer glass has a volume coefficient of expansion much less than that of mercury. Therefore you can ignore the expansion of the glass.