engineers sometimes add chlorine to water in pipes to disinfect water. It is desired to achieve four logs of kill. This means that the effluent concentration of microorganisms is 10^4 times the influent. The flow in the river is 30ft^3/min and the first-order rate constant for disinfection is 6min^-1. 1)What kind of hydrodynamic model should you use? 2) write the mass balance equation for microorganisms in symbols at steady state. define symbols.3) Calculate volume of the pipe required to achieve four logs of kill. 4) If pipe is 3 ft in diameter, how long would the pipe have to be in feet to achieve four logs of kill?