並前往https://sites.google.com/view/econstarjourney/%E9%A6%96%E9%A0%81/%E6%91%98%E6%98%9F%E6%A6%82%E5%BF%B5/%E5%BE%AE%E8%A7%80%E7%B6%93%E6%BF%9F%E8%AA%B2%E9%A1%8C-microeconomics-topics/%E9%9C%80%E6%B1%82%E5%BD%88%E6%80%A7-price-elasticity-of-demand