1. Suppose that from the past experience a professor knows that the test score of a student taking his final examination is a random variable with mean 66 and standard deviation 11. How many students would have to take the examination to ensure, with probability at least 0.94, that the class average would be within 1.5 of 66?
2. A multiple-choice test consists of 29 questions with possible answers of a, b, c, d, e. Estimate the probability that with random guessing, the number of correct answers is at least 11.