(c) The river Sungai Kim in Johor has a flow rate of 76 ms and a velocity of 0.73 m/s. A textile mill in Pasir Gudang Industrial Site dumps its waste into the river. Just downstream from the effluent discharge of the textile mill, the concentration (C) of a green dye used in the textile mill operations is 10 mg/L. This dye is known to degrade according to first order kinction with a rate of 0.25 d. What is the concentration of dye at the intake for the Johore Baharu water treatment plant, which is located 26km downstream? (7 marks)