We are testing the hypothesis that the average gas consumption per day in Billings, Montana is greater than 7 gallons per day; we want 95% confidence.

We sample 30 drivers. The average is 8.4, and the sample standard deviation is 4.29.

Our null hypothesis is

1. What is the Z-value for a 1-tailed test at 95%?

2. What is the Z-value for our sample mean of 8.4?

3. What is the p-value for our sample mean of 8.4?

4. Do we reject the null hypothesis?

Under the null hypothesis, the distribution of a stock price is normal with mean and standard deviation . The actual stock price now is . What is the probability that the stock price is this much or greater under the null hypothesis?

and the sample mean is 12.

Select the answer so that both statements indicate a rejection of the null hypothesis at the 95% confidence level.