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16.10 A site with groundwater contaminated with benzo[a]pyrene has been evaluated for in situ bioremediation. The mass of benzo[a]pyrene in the system is 64 kg , and it must be treated to 0.1 kg . Bioremediation is controlled by benzo[a]pyrene desorption; the rate constant for contaminant desorption is 0.017 day \( ^{-1} \). The site has 24 permanent wells on 3 m centers, which provide sufficient dissolved oxygen throughout the site. Two oxygen sources have been evaluated in benchscale treatability tests. The first option for an oxygen source is a fabric sock filled with magnesium peroxide. The magnesium peroxide lifetime is 60 days, and it costs \( \$ 44 \) to replace. The second option for an oxygen source is pumping air into each of 24 wells. The cost of the air pump, piping, and diffusers is \( \$ 8500 \). The operation cost for the pump is 3.8 \( \mathrm{kW} \cdot \mathrm{h} \) and electricity costs \( \$ 0.11 / \mathrm{kW} \cdot \mathrm{h} \). Determine the cost of each system and select the least-cost option.

Which of the following is the most likely sequence of events an auditor might follow in considering internal control? A. An auditor performs additional tests of controls after the detailed substantive testing has been completed, because it may be more efficient to do so. B. An auditor performs tests of controls first, using the knowledge obtained from those tests to develop an understanding of internal control. C. An auditor performs tests of controls at the same time that he or she is obtaining an understanding of internal control, because it may be more efficient to do so. D. An auditor performs substantive tests prior to tests of controls, because a large number of substantive errors may help the auditor identify areas of weakness.

Calculate the number of moles of C2H6C2H6 in 4.11×10234.11×1023 molecules of C2H6C2H6.

Use the reduction formula ∫sinnxdx=−sinn−1xcosxn+n−1n∫sinn−2xdx to evaluate the integral ∫7sin5xdx. Use C for the constant of integration. Write the exact answer. Do not round..

What is the pH of a 0.82 M NH3 solution? (Kb = 1.8*10-5)

Which embryonic cell type can develop into all cell types within a species? Pseudocoelomate Diploblast Totipotent Indeterminate

Question 2 1 pts Which compound will have the highest boiling point?

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A naturalist is observing the behavior of a frog in a small lily pond. There are four lily pads in the pond, and the frog jumps from one to another. The probability of jumping from any pad to another pad is inversely proportional to the relative distance. The matrix shows the distances: a) Model the frog’s location as a Markov Chain. Provide the state definition and the state space clearly. Provide the transition probability matrix. b) If the frog starts on pad 2, what is the probability that it is on pad 3 after two jumps? c) In the long run, in what fraction of the time the frog is on pad 1? d) Find and interpret all mean first passage times.