Solve using given information

is planned to compare salaries of plant managers in two regions. The plan is to take a sample of 400 plant managers from each region and ask their annual salaries. Assume that previous suggest that 61 = 62 = $5000. Are the sample sizes sufficient to produce a 99% confidence interval on , - H2 having a width of only $1200? e to view page 1 of the standard normal distribution table. e to view page 2 of the standard normal distribution table. le sizes sufficient because the samples would need to be at least people each, which is the planned sample sizes of 400. p to the nearest whole number as needed.)