1.何謂第一級、第二級與第三級差別取價。(10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%)