# Reference us environmental protection agency case

• Homework Help
• 4
• 100% (3) 3 out of 3 people found this document helpful

This preview shows page 2 - 4 out of 4 pages.

(Reference: U.S. Environmental Protection Agency Case Studies Report 832-R-93-005). Chloride compounds as residuals from residential areas are a problem forwetlands. Suppose that in a particular wetland environment the following concentrations (mg/l) of chloride compounds were found: outflow 64.1, seepage 75.8, remaining due to evaporation 23.9, in the water volume 68.2. a) Compute the weighted average of chlorine compound concentration in milligrams per liter (mg/l) for this ecological system.
b) Suppose the EPA has established an average compound concentration target of no more than 58 mg/l. Comment on whether this wetlands system meets the target standard for chlorine compound concentration.
6. Estimate the mean and median of each distribution.
7. Use the histograms to answer the questions. Questions: a) Construct the frequency table for each class. Class BoundariesFrequency for Class 1(number of students)Frequency for Class 2(number of students)29.5-39.51139.5-49.53149.5-59.54259.5-69.56369.5-79.55479.5-89.53789.5-99.526b) Determine the total number of students in each class.
c) Based on the given histograms, which class do you think has the highest mean score? __both ____
d) Which class had the highest median score?
e) Compute the mean score in each class rounded to one decimal place. (Hint: Use the process for computing mean for grouped data.) No need of showing your work on this paper (you’re expected to workit on your scratch paper).