You are living on a lake that has two water streams coming in and one outflow....

 
  

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You are living on a lake that has two water streams coming in and one outflow. The total flow out of the lake is 0.14 m/s and for the inflow: stream one has 1/4 the flow rate of the outflow. The water from stream one is polluted with microplastics (300 g/L). The total volume of the lake is 16,000 m and you can assume it is perfectly well mixed. There are 1,000 L in a m. (a) (6 pts) Draw a picture of this lake/stream system with the flows labeled and write the full mass balance equation. If the system has reached steady state, what is the concentration of microplastics in the outflow? Assume that the microplastics are conserved pollutants and there are no other losses or sources for them in the lake or streams. (d) (8 pts) Assume that the filters get clogged and need to be replaced once a year. You want to budget how much you will need in today's dollars to invest to maintain this cleanliness of water. What is the cost for the next 20 years assuming an interest rate of 8% and an upfront cost for one entire system (filter + mount) of $500? Each filter replacement will cost $70 and you can assume that you are working with whole numbers (if you have less than a full number of filter systems calculated in part c, round up). If the cost to remove this pollutant stream for the factory is a total cost of $10 k, give an argument for them to make this change. (Note: complete the calculation and then use that in your short argument - this should not be more than a few sentences.) You are living on a lake that has two water streams coming in and one outflow. The total flow out of the lake is 0.14 m/s and for the inflow: stream one has 1/4 the flow rate of the outflow. The water from stream one is polluted with microplastics (300 g/L). The total volume of the lake is 16,000 m and you can assume it is perfectly well mixed. There are 1,000 L in a m. (a) (6 pts) Draw a picture of this lake/stream system with the flows labeled and write the full mass balance equation. If the system has reached steady state, what is the concentration of microplastics in the outflow? Assume that the microplastics are conserved pollutants and there are no other losses or sources for them in the lake or streams. (d) (8 pts) Assume that the filters get clogged and need to be replaced once a year. You want to budget how much you will need in today's dollars to invest to maintain this cleanliness of water. What is the cost for the next 20 years assuming an interest rate of 8% and an upfront cost for one entire system (filter + mount) of $500? Each filter replacement will cost $70 and you can assume that you are working with whole numbers (if you have less than a full number of filter systems calculated in part c, round up). If the cost to remove this pollutant stream for the factory is a total cost of $10 k, give an argument for them to make this change. (Note: complete the calculation and then use that in your short argument - this should not be more than a few sentences.)