In a certain region, many of the residents are employed by the oil industry. Economists in the region investigated the difference between the salaries of those who work in oil-field jobs and those who work in non-oil-field jobs. Salaries were recorded for a random sample of 84 workers from the 1,200 oil-field workers and a random sample of 72 workers from the 50,000 non-oil-field workers in the region. A 95 percent confidence interval for μO−μN, where μO is the mean salary of all jobs of oil-field workers and μN is the mean salary of all jobs of non-oil-field workers, will be constructed. Have the conditions for inference with a confidence interval been met?