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1. Assume we know that the population standard deviation of income in the United States (σ)...

1. Assume we know that the population standard deviation of income in the United States (σ) is $12,000. A labor economist wishes to test the hypothesis that average income for the United States exceeds $64,000. A random sample of 900 individuals is taken and the sample mean is found to be $65,000. Test the hypothesis at the 0.05 level of significance. What is the p-value of the test statistic?

2. A bank executive believes that average bank balances for individuals equals $15,000. The executive takes a random sample of 25 individuals and finds a sample mean of $12,800 and a sample standard deviation (s) of $4,000. Test the hypothesis at the 0.05 and 0.01 levels.

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