What is the null hypothesis

A social psychologist predicted that ratings of an individual’s social desirability would be influenced by their…

A social psychologist predicted that ratings of an individual’s social desirability would be influenced by their physical attractiveness. Participants received photos of attractive, average, or unattractive individuals. The researcher found that the more attractive the individual, the higher their rating of social desirability. This difference was significant at the .05 level. 1. What is the null hypothesis? 2. What is the research hypothesis? 3. What would be the Type I error? 4. What would be the Type II error? 5. What is the probability of a Type I error?