Corporate sustainability refers to business practices designed around social and environmental considerations. In a study on the sustainability behaviors of CPA corporations, 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. Higher point values indicate a higher level of support for sustainability. The following summary statistics are obtained for the data.

Sample Mean=66.87; Sample standard deviation=23.49.

a.Use the sample mean and standard deviation to calculate the 95% confidence interval for the mean level of support for all senior managers at CPA firms.

b.Give a practical interpretation of the 95% confidence interval.

c.Suppose the CEO of a CPA firm claims that the true mean level of support for sustainability is 75 points. Do you believe this claim? Explain.