Some manometers are constructed as in the figure at right, with one large reservoir and one small tube open to the atmosphere. We can then neglect movement of the reservoir level. If the reservoir is not large, its level will move, as in the figure. Tube height his measured from the zero-pressure level, as shown. To measurement 2 (a) Let the reservoir pressure be high, as in the Figure, so its level goes down. Write an exact Expression for pigage as a function of h, d, D, and gravity g. (b) Write an approximate expression for pigage, neglecting the movement of the reservoir. (c) Suppose h = 26 cm, pa = 101 kPa, and pm = 820 kg/m. Estimate the ratio (D/d) required to keep the error in (b) less than 1.0% and also < 0.1%. Neglect surface tension.