de Not yet graded (Short Answer - No Computation) A computer manufacturer estimates that its line of minicomputers has on average, 8.4 days of downtime per year. To test this claim, a researcher contacts seven companies that own one of these computers and is allowed to access company computer records. It is determined that, for the sample the average number of downtime days is 5.6, with a sample standard deviation of 1.3 days. Assuming that number of downtime days is normally distributed, test to determine whether these minicomputers actually average 8.4 days of downtime in the entire population. Let a =0.01. (a) State the null hypothesis and the alternative hypothesis. (b) Which test statistics is appropriate and why? () in complete sentences, state the Type I and Type Il errors