9) an experiment has been performed to determine the porosity of an unconsolidated sandpack. distilled water was poured into a graduated cylinder to a height h . fine sand of average grain size of 150 um was poured into the graduated cylinder to a height hy to form the sandpack. it was found that the water in the graduated cylinder rose to a height h2 after the sand was poured into the cylinder. a. derive the expression for the porosity of the sandpack in terms of h, and h2. b. given hı = 5 cm and h2 = 8 cm, calculate the numerical value of the porosity of the sandpack. c. what is your best estimate of the permeability of the sandpack? give a numerical answer and briefly outline how you made the estimate.