Two crews are to start at opposite ends of a mountain

Reference no: EM13531114

1.A standard five-day BOD test is run using a mix consisting of fourparts distilled water and one part wastewater (no seed). Theinitial DO of the mix is 9.0 mg/L, and the DO after five days isdetermined to be 1.0 mg/L. What is BOD5 ?

2.Two crews are to start at opposite ends of a mountain and dig a tunnel through the mountain. The slower crew could complete the tunnel in 22 months working alone, and the faster crew could complete the tunnel in 12 months working alone. If the slow crew works for 4 months before the fast crew starts, how many months will the crew have to work before the two crews meet and complete the tunnel.

Reference no: EM13531114

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Two crews are to start at opposite ends of a mountain : A standard five-day BOD test is run using a mix consisting of fourparts distilled water and one part wastewater (no seed). Theinitial DO of the mix is 9.0 mg/L, and the DO after five days isdetermined to be 1.0 mg/L. What is BOD5 ?

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