2.畫圖說明政府如何利用排污費(emission charge)解決外部成本的問題。(15分)

2. Given sorting problem µ convex hull，which one of the following statements can be derived ?(Choose one) (1) The Lower Bound of convex hull is W(n log n). (2) The Lower Bound of convex hull is W(n). (3) The Lower Bound of Sorting is W(n log n). (4) The Lower Bound of Sorting is W(n). Please explain how to find the lower bound by problem transformation. (20%)