For this case the first thing you should do is to see the values of the domain and range of the function where there was a major change. We observe that for x = 1940 we have the value of y = 340. For x = 1950 we have the value of y = 470. The change was: 470 - 340 = 130 During this period there was the greatest growth of the population. Answer: Vermont's urban population increase the most in: 1940 to 1950