Use the following sample sizes and numbers of successes for the next six questions.
Medical researchers reviewing the risk of death for elderly patients taking
dementia drugs found the following data. Assume a .05 significance level for
testing the claim that the proportions are not equal. Also, assume the two simple
random samples are independent and that the conditions are
satisfied.
-Construct a 95% confidence interval for the difference between the two proportions.

Use the following data for the next questions. Biologists, researching the effects
of adding limestone sand as buffer for acid rain effects in streams, monitored the
pH levels of two streams each month for 36 months. The first stream had a mean
pH level of 6.8 with a standard deviation of 2.3. The control stream had a mean pH
level of 9.2 with a standard deviation of 1.5. Assume a .05 significance level for
testing the claim that the mean pH of the first stream was less (more acidic) than
the mean pH of the control stream. Also, assume the two samples are independent
simple random samples selected from normally distributed populations.
-Identify the null hypothesis and alternative hypothesis for the claim that the pH level in the first stream has a standard deviation different from that in the second stream.

Determine the number of successes x suggested by the given statement.
-70% of 300 osteoporosis patients surveyed said they would prefer to take a monthly pill as compared to a daily or weekly pill.