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The concentration of benzene was measured in units of milligrams per liter for a smiple random...

The concentration of benzene was measured in units of milligrams per liter for a smiple random sample of 10 specimans of untreated wastewater produced at a gas field. The sample had an average of 7.15 with a standard deviation of 1.01. Another simple random sample of 6 specimans of treated wastewater had an average of 3.1 with a standard deviation of 1.65. It has been confirmed that both samples come from a normal distribution. Can you conclude that the true average benzene concentration is less in the treated water than in the untreated water? Use a 1% significance to decide.
Group 1: Treated Water
Group 2: Untreated Water
Round to the fourth

find p-val

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