A random sample of 155 households in Whatcom County

1. A random sample of 155 households in Whatcom County yielded an average household income of $51,822, with a sample standard deviation of $2,150. Assume the distribution of household income is Normal. a. Use this information to compute a 90% confidence interval for the population mean household income in Whatcom County. Please clearly list and show that you checked to make sure the data meet all necessary conditions for inference. b. Interpret the meaning of the confidence interval you found in part a in the context of this application. 2. In a recent survey, 319 out of 375 randomly selected Whatcom County residents indicated they had broadband internet access at their home. a. Use this information to compute a 85% confidence interval for the population proportion of Whatcom County residents who have broadband internet access at their home. Please clearly list and show that you checked to make sure the data meet all necessary conditions for inference. b. Interpret the meaning of the confidence interval you found in part a in the context of this application.