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 4580 women was conducted at 34 medical centres. Half of the women took placebos and half took a prescription drug, a widely prescribed type of hormone replacement therapy. There were x, = 41 cases of dementia in the hormone group and X2 = 22 in the placebo group. Is 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.) 1-2. Null and alternative hypotheses: O Ho: (P, - P2) 0 O Ho: (P, - P2) - 0 versus Ha: (P, - P2) 0 O Ho: (0, - P2) + 0 versus Ha: (P1 - P2) = 0 3. Test statistic: z = 4. Rejection region: If the test is one-tailed, enter NONE for the unused region. z > -1645 X 2