A student began experiment for determination of 5-day, 20 C BOD on Monday. Since the 5th day fell on Saturday, the final DO readings were taken on next Monday. On calculation, BOD (i.e. 7 day, 20 C) was found to be 150 mg/L. What would be the 5-day, 20 C BOD (in mg/L)? Assume value of BOD rate constant (k) at standard temperature of 20 C as 0.23/day (base e).

A student began experiment for determination of 5-day, 20 C BOD on Mo

1.	A student began experiment for determination of 5-day, 20 C BOD on Monday. Since the 5th day fell on Saturday, the final DO readings were taken on next Monday. On calculation, BOD (i.e. 7 day, 20 C) was found to be 150 mg/L. What would be the 5-day, 20 C BOD (in mg/L)? Assume value of BOD rate constant (k) at standard temperature of 20 C as 0.23/day (base e).
A.	129 mg/L
B.	127 mg/L
C.	128.0979 mg/L
D.	128 mg/L
Answer» D. 128 mg/L

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A student began experiment for determination of 5-day, 20 C BOD on Monday. Since the 5th day fell on Saturday, the final DO readings were taken on next Monday. On calculation, BOD (i.e. 7 day, 20 C) was found to be 150 mg/L. What would be the 5-day, 20 C BOD (in mg/L)? Assume value of BOD rate constant (k) at standard temperature of 20 C as 0.23/day (base e).
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