SSC JE Civil Engineering 2018 Set 4 Solved Paper

A 45 cm diametre well penetrates an unconfined aquifer of 30 m thick. Under the steady pumping rate for a long time, the drawdown’s at two obser vation wells 10 m and 20 m from the pumping well are 5 m and 3.5 m respectively.
What will be the discharge (cubic metre), if the permeability of the aquifer is given as 20 m/day?