Ultimate BOD of a river water sample is 20 mg/L. BOD rate constant (natural log) is 0.15 day-1. The respective values of BOD (in%) exerted and remaining after 7 days are:

Ultimate BOD of a river water sample is 20 mg/L. BOD rate constant (na

1.	Ultimate BOD of a river water sample is 20 mg/L. BOD rate constant (natural log) is 0.15 day-1. The respective values of BOD (in%) exerted and remaining after 7 days are:
A.	45 and 55
B.	55 and 45
C.	65 and 35
D.	75 and 25
Answer» D. 75 and 25

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Ultimate BOD of a river water sample is 20 mg/L. BOD rate constant (natural log) is 0.15 day-1. The respective values of BOD (in%) exerted and remaining after 7 days are:

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