A two-tailed hypothesis test of the population mean is used when the alternative hypothesis takes the form 
Definitions:
Marijuana
A psychoactive drug from the Cannabis plant intended for medical or recreational use, known for its relaxing and, in some cases, euphoric effects.
Marijuana Use
The practice of using cannabis, a mind-altering substance, either for pleasure or health reasons.
Wish-Fulfillment Theory
A psychological theory suggesting that dreams represent the unconscious desires and wishes of the dreamer.
Manifest Content
In psychoanalysis, the manifest content is the literal storyline or surface meaning of a dream, as remembered by the dreamer.
Q11: What would be the lower limit of
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Q48: A two-tailed hypothesis test of the population
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Q138: The null hypothesis is a vehicle for
Q176: The t distribution allows the calculation of
Q208: The mean of the sampling distribution of