Details: Refer to the OECD data, which reports information on census, economic, and business data for 29 countries.
a. Develop a 90 percent confidence interval for the mean percent of the population over 65 years.
b. Develop a 90 percent confidence interval for the mean energy use.
Z value for 90% confidence = 1.28 ( Normal Tables)
<br>90% confidence Interval = (Mean - Z* Std Dev , Mean + Z* ...