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PROBLEMS (SI) 2.17 For the situation sketched below, the following information is known: P0 kg/m', PH, = 13 590.0 kg/m', g=9.8 m/s-2, p,-500 kPa. Determine Pn. 1000.0 H,0 2 m 0.4 m 0.5 m -II Hg Problem 2.17 2.18 The piston shown above is held in equilibrium by the pressure of the gas flowing through the pipe. The piston has a mass of 21 kg; P= 600 kPa; P= 170 kPa. Determine the pressure of the gas in the pipe, Pm- 10 cm+ 20 cm II Problem 2.18 2.19 Referring to Problem 2.18, p= 350 kPa, Pa=130 kPa, Pu=210 kPa. Find the mass of the piston. 2.20 A new temperature scale is proposed where the boiling and freezing points of water at atmospheric pressure are 500X and 100X, respectively. Determine absolute zero for this new temperature scale.