A hydrometer is an instrument for measuring the specific gravity of a liquid. For example, vintners use a hydrometer to determine the density changes as wine is fermented, and producers of maple sugar and maple syrup use the hydrometer to find how much sugar is in the collected sap. Markings along a stem are calibrated to indicate the specific gravity for the level at which the hydrometer floats in a liquid. The weighted base ensures that the hydrometer floats vertically. Suppose the hydrometer has a cylindrical stem of cross-sectional area 0.400 cm2. The total volume of the bulb and stem is 8.80 cm 3 and the mass of the hydrometer is 4.80 g.
(a) How far from the top of the cylinder should a mark be placed to indicate a specific gravity of 1.00?
(b) When the hydrometer is placed in alcohol, it floats with 7.25 cm of stem above the surface. What is the specific gravity of the alcohol?
(c) What is the lowest specific gravity that can be measured with this hydrometer?

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Hydrometer Fluid to be tested