Coagulation is a process in wastewater treatment where chemicals are added to the water to make tiny particles stick together, forming bigger clumps called flocs. Coagulant doses affect water turbidity. Too little causes high turbidity, while too much can lead to excessive floc formation and additional turbidity. Finding the right coagulant dose is crucial for optimal turbidity removal in water treatment. Table I shows the coagulant doses and their effects on water turbidity that you obtained at your industrial effluent treatment system (IETS). Table 1 Coagulant dose, C (mg/L) Remaining turbidity, T (NTU) 3 19.6 5 13.5 9.8 6.7 4.9 4.8 7 9 11 13 15 17 19 21 6.1 8.3 11.3 14.9 a) Your boss asks you to explain the effect of the coagulant dose on water turbidity, mathematically. Develop a best-fit equation for the relationship between water turbidity and coagulant dose using Nave-Gauss elimination method. b) Determine the coefficient of determination for the equation. c) Determine the water turbidity to the most accurate value when 10 mg/L of coagulant is added to the water. At any given circumstance, the maximum turbidity level is 5 NTU. Does the coagulant dose yield an acceptable turbidity value? d) You have been working excellently for a year, but your boss does not give you a bonus. To show your frustration, you plan to use as much coagulant as you can, but you will not compromise the turbidity value. Determine the coagulant dose needed if the permitted turbidity value is 7 NTU. In any relevant method, use 0.05% as the stopping criterion. e) You are now a competent person monitoring the IETS at your plant. Despite the frustration of not getting the annual bonus, you know that you cannot simply use extra coagulant because the additional turbidity might exceed the acceptable level. In that case, determine the amount of coagulant that gives you the lowest turbidity value. In any relevant method, use 0.1% as the stopping criterion.