The Boulder Fire Department conducted a study of average emergency response times for its two stations. For a sample of 125 emergency responses by the North Boulder Station, average response time was 16.2 minutes. For a sample of 160 emergency responses by the South Boulder Station, average response time was 14.3 minutes. Are these sample results sufficient to reject a “no difference in (population) average response times “null hypothesis at the 5% significance level? Assume the population standard deviations are known: 4.5 minutes for the North Boulder Station and 5.2 minutes for the South Boulder Station.