According to annual precipitation data available for the past 75 years, the average precipitation in New York City was 41.76 inches per year and the observed sample standard deviation was 5.74 inches per year. (a) Construct a 99% confidence interval for the true mean value NYC of the distribution of yearly precipitation in New York City. (b) Determine the required sample size in order to estimate NYC to within 1.2 inches at the 99% confidence level. (c) During the same 75-year period, the average precipitation in Tokyo was 34.37 inches per year and the observed sample standard deviation was 4.98 inches per year. Find a 95% confidence interval (CI) for the difference between the mean yearly precipitation in New York uNYC and Tokyo uTOK. Next, compare the 95% CI to the 99% CI for the same difference uNYC - uTOK.

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