In the last few years, many research studies have shown that the purported benefits of hormone replacement therapy (HRT) do not exist, and in fact, that hormone replacement therapy actually increases the risk of several serious diseases. A four-year experiment involving 4448 women was conducted at 33 medical centres. Half of the women took placebos and half took a prescription drug, a widely prescribed type of hormone replacement therapy. There were x1 = 45 cases of dementia in the hormone group and x2 = 22 in the placebo group. 15 there sufficient evidence to indicate that the risk of dementia is higher for patients using the prescription drug? Test at the 1% level of significance. (Round your answers to two decimal places.) 12. Null and alternative hypotheses: O .i-10:(p1 7 p2) = 0 versus Ha: (p1 7p?) i O O HO: (p1 p2) : 0 versus Ha: (pl 7.02) O O HO: (p:L 7 p2) O 3. Test statistic z : S 4. Rejection region: If the test is one-tailed, enter NONE for the unused region. B: 2.: 5. Conclusion: 0 H0 is rejected. There is sufficient evidence to indicate that the risk of dementia is higher for patients using the prescription drug. 0 H0 is not rejected. There is insufficient evidence to indicate that the risk of dementia is higher for patients using the prescription drug. O H0 is rejected. There is insufficient evidence to indicate that the risk of dementia is higher for patients using the prescription drug. 0 H0 is not rejected. There iS sufficient evidence to indicate that the risk of dementia is higher for patients using the prescription drug. An experiment was conducted to test the effect of a new drug on a viral infection. After the infection was induced in 100 mice, the mice were randomly split into two groups of 50. The first group, the control group, received no treatment for the infection, and the second group received the drug. After a 307day period, the proportions of survivors, p1 and 12, in the two groups were found to be 0.38 and 0.60, respectively. (a) Is there sufficient evidence to indicate that the drug is effective in treating the viral infection7 Use a : [1.05. State the null and alternative hypotheses. O H0: (01 7 p2) : 0 versus Ha:(p17 p2) D 0: (D1 7 p2) 0 versus Ha: (pl 7 p2) = 0 Find the test statistic and rejection region. (Round your answers to two decimal places If the test is one7tailed, enter NONE for the unused region.) test statistic z : |: rejection region 2 > I: z