A sandy soil is tested for permeability using the constant head method. The diameter of the soil column is 8.0 cm, the length of the soil column is 16.0 cm. The hydraulic head loss across the soil specimen is 6.4 cm. Over a period of 3 min, 350 mL of water is collected at the downstream side of the soil specimen. What is the permeability of the soil specimen in cm/sec?