Refer to the Business and Society (March 2011) study on the sustainability behaviors of CPA corporations, Exercise 6.12. Recall that the level of support for corporate

sustainability (measured on a quantitative scale ranging from 0 to 160 points) was obtained for each in a sample of 992 senior managers at CPA firms. The data (where higher point values indicate a higher level of support for sustainability) are saved in the accompanying file. The CEO of a CPA firm claims that the true mean level of support for sustainability is 75 points.
a. Specify the null and alternative hypotheses for testing this claim.
b. For this problem, what is a Type I error? A Type II error?
c. The XLSTAT printout shown above gives the results of the test. Locate the test statistic and p-value on the printout.
d. At α = .05, give the appropriate conclusion.
e. What assumptions, if any, about the distribution of support levels must hold true in order for the inference derived from the test to be valid? Explain.

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XLSTAT 2016.04.azz29 - One-sample t-test and z-test Theoretical meac 75 Signilicance level (:5 Summary statistics Summary statistics: Varlable Support Observations Minimum Maximum Mean Std. devlation 992 0.000 155.000 67.755 26.871 One sample z test /Two-tailed test: 5% confidence Interval on the mean: (46.083, 69A27) Difference z(Observed value) lel (Citical value) pvalue (Two-talled) alpha 1.2450 -8.4929 1.9600 <0,0001 0.05 Test interpretation: H0: The difference between the means is equal to a Ha: The difference between the means is different from 0. As the computed p-value is lower than the significance level alpha 0.05, one should reject the mull hypothesis H0, and accept the alternative hypothesis Ha. The risk to reject the null hypothesis H0 while it is trueis lower than 001%.