1. ABC Corporation makes cardboard boxes. Fifty-five randomly selected such boxes were loaded until they broke. The average breaking capacity of these boxes was found to be 78.52 pounds. Suppose that the standard deviation of the breaking capacities of all such boxes is 2.63 pounds. Calculate a 99% confidence interval for the average breaking capacity of all boxes of this type. Draw graph
2. The president of a university claims that the mean time spent partying by all students at this university is exactly 7 hours per week. A random sample of 25 students taken from this university showed that they spent an average of 9.50 hours partying the previous week with a population standard deviation of 2.3 hours. Test at the 5% significance level whether the president's claim is true. Explain your conclusion in words.