A random sample of 54 students from a college are selected from a normal population with mu equal to 20 and sigma equal to 5. After a treatment is administered to the students, the researcher calculated the sample mean to be 21. Is there enough evidence to conclude that the treatment had a significant effect at the 5% significance level?  How many tails does this test have

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A: z-score for sample mean: From the given information,   n=16 µ=100 σ=32 x-bar=127   Therefore,

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Q: Citrus Rental is a popular car rental agency that has a history of having too few cars available, so…

A:

Q: ferroni Correc

A: Given,

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A: Solution:

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