In each of the following scenario, determine the appropriate test statistics to be used. (z-test, t-test, F-ratio test. Chi-square test).

1. Independent random samples of 7 doctors from Hospital A and Hospital B were asked to assess the personality aspect of their medical representatives on a scale of one (poor) to ten (excellent). For the doctors of Hospital A, the mean rating was 7.345 and the sample standard deviation was 0.794. For the doctors of Hospital B, the mean rating was 7.543 with a standard deviation of 0.549. Test the hypothesis at 0.01 significance level that the population mean ratings for these two groups of doctors are the same.

2. A manufacturer of cellphone batteries took a random sample of 150 batteries from a day's production used them continuously until they failed to work. The average life, as measured by the number of days until failure, was 96 hours with a standard deviation of 5 hours. At 0.005 level of significance, is there evidence that the mean life of the batteries is more than 90 hours?

3. A CD outlet near the University claims that they are patronized by an equal number of male and female students. A random sample of 60 student customers are selected and surveyed. Of these, 35 are female. Is there enough evidence to accept the claim at 5% level of significance?

4. A stock portfolio predicts that the average rate of return for common stocks in the stock market at the end of this year will increase no more than 5% over last year. A financial analyst believes that the rate will rise by more than the predicted rate. A random sample of 25 stocks shows an average increase of 5.3% over last year with a standard deviation of 1.6%. Are we to concur with the financial analyst's belief?

5. The CEO of a big corporation wants to analyze the average financial aid given to its three subsidiaries on their short-term project in a period of three years. He tests his assumption at 0.05 level of significance. What can be concluded from the following table?