The Concentration of Hexane (A Common Solvent) Was Measured in Units

question 97

Multiple Choice

The concentration of hexane (a common solvent) was measured in units of micrograms per liter for a simple random sample of nineteen specimens of untreated ground water taken near a municipal landfill. The sample mean was $508.4$ with a sample standard deviation of 4.3. Sixteen specimens of treated ground water had an average hexane concentration of $506.1$ with a standard deviation of 4.7.
It is reasonable to assume that both samples come from populations that are approximatel normal. Can you conclude that the mean hexane concentration is less in treated water thar untreated water? Use the $\alpha = 0.01$ level of significance.

• A) No
• B) Yes

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Definitions:

Erectile Disorder

A dysfunction characterized by difficulties with obtaining an erection during sexual activity, maintaining an erection until the completion of sexual activity, and/or a marked decrease in erectile rigidity in about 75 to 100 percent of sexual occasions over a period of at least six months, leading to distress.

Sexual Dysfunctions

A variety of disorders classified by difficulties experienced during any stage of a normal sexual activity, including desire, arousal, or orgasm.

Sexual Pain Disorder

A condition characterized by significant pain during intercourse that is not caused exclusively by lack of lubrication or by other medical conditions.

Sexual Desire Disorder

A condition marked by a lack or absence of sexual desires or fantasies, which can significantly affect relationships and emotional health.