medical test is conducted to determine whether or not a new vaccine reduces the complications of dengue fever . State the null and alternative hypothesis Ho : Ha :

Suppose data shows that only 50% of breast cancer patients can survive more than 5 years. You suspect the percentage is too low, so you'd like to conduct a study to examine this situation. What is the null and alternative hypothesis in this situation?

Dr. Luo hypothesizes that wives are happier than their husbands. She measured a group of married couples’ marital happiness and the data are as follows: couple                Wives                 Husbands    1                       98
                        93                 2                       94
                        90                 3                       96                        95                 4                       91                        92                 5                       97                        95                 6                       97                        91                a. Are wives significantly happier than their husbands in the marriage? Use alpha = .05. 
 b. If Dr. Luo decided to reject the null hypothesis (assuming she was completely correct in calculations), what is the probability that she made a Type I error?

A researcher administers a new treatment to a sample of participants selected from a population with µ = 80. If the researcher obtains a sample mean of M = 88, which combination of factors is most likely to result in rejecting the null hypothesis?