Hello can someone help me with this assignment 1. Identify four…

Hello can someone help me with this assignment 1. Identify four…

Hello can someone help me with this assignment(a) Seafood (b) Urban air (c) Drinking water

1. Identify four possible risk agents in each:

List their permissible limits, carcinogenic and/or non-carcinogenic effects with proper citation.

2. Tabulate (a) sources (b) cancer slope factors for different pathways; (b) RfD and/or RfC values (if available); and (c) Human health effects from benzene, cadmium, arsenic, dioxin, carbon tetrachloride, and nickel.

3. A health insurance company believes that people can be divided into two classes: those that are affected by some chronic diseases and those that are not. Their statistics show that the chronic diseases person will have a chronic disease at some time within a fixed 1-year period with probability 0.4, whereas this probability decreases to 0.2 for a non-chronic diseases person. If we assume that 30 percent of the populations have chronic diseases, what is the probability that a new policy holder will have a chronic disease within a year of purchasing a policy?

4. Consider the system shown in the following figure which consists of three valves, a pump, a pipeline, and a tank to collect water pumped from the pond. Construct a fault tree corresponding to the top event: “no flow of water into the tank”

3. An industrial complex is located near two towns: town A with 50,000 populations and town B with 35,000 populations. The wind rose diagram based on long-term meteorological records shows that 24% of the time, the wind direction from the industrial complex is towards town A and the remaining time it is towards town B. The statistical data on the chemical release shows that 20% of the time the emission from the industrial complex reaching to the town A is of concern to human health with 40% chances to aggravate respiratory problems. On the other hand, 35% of the time, the emission from the industrial complex reaching to the town B is of concern to human health with 12% chances to aggravate respiratory problems. Draw an event tree diagram with probability number on the nodes. List assumptions are made in your estimate, if any.

4. Water samples collected in a stream on monthly basis were tested for COD for a year shows skewness in the data. The concentration levels in mg/l are as follows: 55, 43, 38, 62, 101, 78, 125, 85, 72, 91, 68, and 31. If log-normal distribution is used, determine the probability if (a) COD level exceeds 70 mg/l; (b) COD level is between 75 mg/l and 85 mg/l; and (c) COD is less than 90 mg/l.