(a) How does the time path of rD(t)/y(t) look like? (b) What is the steady-state value of rD(t)/y(t)? (c) Does it exceed one? Interpret your result.

I leave a like on all sections for your assistance, thank you.WATER TREATMENT PLANT PROCESS COSTSInformation: (Please see the attached image depicting the schematics + Text)  The results obtained from the four operating modes showed that the hardness decreased by 4.7% when both processes were in operation (i.e., sludge recirculation and aeration). When only sludge was recirculated, the reduction was 3.8%. There was no reduction due to aeration only, or when there was neither aeration nor recirculation. For turbidity, the reduction was 28% when both recirculation and aeration were used. The reduction was 18% when neither aeration nor recirculation was used. The reduction was also 18% when aeration alone was used, which means that aeration alone was of no benefit for turbidity reduction. With sludge recirculation alone, the turbidity reduction was only 6%, meaning that sludge recirculation alone actually resulted in an increase in turbidity-the difference between 18% and 6%. Since…

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Let f(t) be the balance in a savings account at the end of t years and suppose y = f(t) satisfies the differential equation y' = 0.05y - 12,500. (a)Suppose that after one year the balance is $230,000. Is the balance increasing or decreasing at that time? At what rate is it increasing or decreasing at that time? (b)Write the differential equation in the form y' = k(y - M). (c)Describe the differential equation in words. %3D %3D (a) The balance is decreasing at a rate of $ - 1000 per year. (b) y' = .05(y - 230000) (c) Choose the correct answer below. A. The rate of change of the savings account balance is proportional to the balance at the end of t years and is always increasing. B. The rate of change of the savings account balance is proportional to the difference between the balance at the end of t years and $250,000. C. The rate of change of the savings account balance is proportional to the balance at the end of t years and is always decreasing. D. The differential equation gives the…