The grаph belоw shоws chаnges in а pоpulation of wild sheep that were introduced to the island of Tasmania in the early 1800's. The horizontal axis is labeled year from 1820 to 1940 with tick marks in increments of ten. The vertical axis is labeled number of sheep in thousands from zero to two thousand five hundred, with tick marks in increments of 500. The population curve starts at zero in 1820, increases slowly then increases rapidly to two point two five million by 1850. This increase is enclosed in a bracket. After 1850 the population curve fluctuates between two point two five million and one point two five million, with a horizontal dashed line through the middle of these population fluctuations. The graph indicates that the sheep population most likely is