QUESTION 1 Water is palatable and potable once it has the magnificient characteristics due to its physical, chemical and biological characteristics. a) Define BOD and COD by your own words. [2 Marks] b) List the physical properties of the water that makes it considered as polluted. [4 Marks] c) A wastewater treatment plant diposes of its effluent in a surface stream. Characteristics of the stream and effluent are shown in Table 1: Table 1 Wastewater Stream Flow, m/h 0.2 5.0 Initial Dissolved Oxygen, mg/L in 200mL 2 0 Final Dissolved Oxygen, mg/L in 200mL 60 10 (5 days) Temperature, C K1 at 20C, day- 15 20.2 0.2 K2 at 20C, day' i) 0.3 63 Calculate the concentration of dissolved oxygen of the stream after 5.0 days. [5 Marks] ii) Determine the minimum dissolved oxygen concentration as a result of the waste discharge and draw the disolved oxygen balance diagram to demonstrate the journey of the mixed waters.