please answer this.

Question 4 Open with Google Docs Let X1; ..., X100 be a random sample from a normal distribution with mean / and variance o2. Suppose x = 10 and s = 10. 1. (10 points) Find a 85% confidence interval for / 2. (10 points) Test Ho : / = 8 versus HA : M # 8 at the 5% significance level 2 3. Imagine you are instead interested in testing Ho : M = 8 versus HA : M > 8. Somebody tells you that the best approach would be to reject the null hypothesis if the sample mean is above 9.96. . (5 points) What would the probability of type I error be? . (5 points) What is the power of this test if / is actually equal to 10