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Question 2: Wenner four poles equal method is used to measure the soil resistivity near a 66/11 kV substation using a AEMC 6472 Ground Tester. The readings are recorded at 1, 2, 3, 4 and 5 m intervals of the probe distance. The corresponding soil resistance were measured to be 16.4, 5.29, 3.05, 1.96 and 1.36 1, respectively. Calculate the average soil resistivity in that substation. Question 3: Alexander touches an energized tower for 0.3 s and his body weight is 70 kg. The resistivity at the surface layer and at a distance of 0.3 m inside the soil are found to be 70 and 50 12-m, respectively. Determine the surface layer derating factor, touch and step potential. a Question 4: Robinson touches an energized tower for 0.5 s. The surface layer derating factor is found to be 0.75 for a soil resistivity 300-m at a distance 0.05 m inside the soil. Find the surface layer resistivity, touch and step potential if the body weight of the Robinson is 50 kg.