A real estate agent agrees to sell an apartment complex according to the following commission$$ schedule: $$$$30,000$ plus $30\%$ of the selling price in excess of $$$$850,000.$ Assuming that the complex will sell at some price between $$$$850,000$ and $$$$1,100,000$inclusive$,$ over what range does the$$ agent's commission$$ vary? How does the commission vary as a percent of selling$$ price?