You are investigating an unconfined sand aquifer. The following data have been collected from a slug test of the aquifer, recording the depth to water in a monitoring bore before and after the slug was inserted into the bore (at time = 0): Time (seconds) Depth to water (meters) h/ho Pre-test 2.86 0 (test start) 1.46 1.75 1.97 10 2.19 15 2.34 20 2.46 30 2.62 60 (test end) 2.79 Le/R ratio: ho value: The bore was made of PVC, with a screened interval from 6.50 to 8.50 m below the ground surface. The borehole has a diameter of 60 mm. It can be assumed that the effective radius is the same as the borehole radius. a) Calculate the values required to estimate hydraulic conductivity using an appropriate method, completing the table above (3 marks) b) Estimate the hydraulic conductivity of the aquifer in m/day, showing all working and using appropriate significant figures (4 marks) c) Explain any limitations associated with this method of estimating hydraulic conductivity (K), and name one alternative method to estimate hydraulic conductivity (3 marks)