Consider the discharge of an oxygen demanding waste to a river. Qualitatively assess the impact of the following change on the resulting dissolved oxygen concentration in the river. Will the dissolved oxygen concentration increase or decrease because of the change? Explain your answer.

Consider the discharge of an oxygen demanding waste to a river. Qualitatively assess the impact of the following change on the resulting dissolved oxygen concentration in the river. Will the dissolved oxygen concentration increase or decrease because of the change? Explain your answer.

Structural Analysis

6th Edition

ISBN:9781337630931

Author:KASSIMALI, Aslam.

Publisher:KASSIMALI, Aslam.

Chapter2: Loads On Structures

Section: Chapter Questions

Problem 1P

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Answer and show complete solution. Pls don't rejectA factory discharges waste water to a nearby river. The concentration of dissolved oxygen (DO) a few meters downstream of the factory’s discharge point was recorded for 10 consecutive days as shown in the table below. The lower the DO, the more “polluted” the river is and as the DO reaches zero, the river becomes unable to sustain marine life. Day DO (milligram/liter) 1 1.8 2 2 3 2.1 4 1.7 5 1.2 6 2.3 7 2.5 8 2.9 9 1.9 10 2.2 a. Local environmental regulations prescribe a minimum DO concentration of 2.0 mg/L. Perform a hypothesis test to determine whether the river’s water quality satisfies local regulations at a 5% significance level. (follow the 8step hypothesis test)b. Assume that the daily DO concentration is normally distributed. Estimate the values of the parameters μ and σ.c. Determine the 95% confidence interval for the true mean DO concentration.
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