Phân tích lỗi dùng từ trong những câu sau và sửa lại cho đúng. 1. Trực ca này là một ông bác sĩ già, nhiều tuổi. Ông lẩm bẩm.

Linux is distributed under gnu gpl. why is this important? a. it ensures that only torvalds can profit from the sale of linux b. it prevents unknowledgeable users from downloading programs they don't know how to operate. c. it provides protection for the developers who created linux. d. it states that anyone can copy, modify, and share the program if changes are made public.

Where would you click to edit the chart data?

Suppose there is a relation r(a, b, c) with a b+-tree index with search keys (a, b).1. what is the worst-case cost of finding records satisfying 10 < a < 50 using this index, in terms of the number of records n1, retrieved and the height h of the tree? 2. what is the worst-case cost of finding records satisfying 10 < a < 50 and 5 < b < 10 using this index, in terms of the number of records n2 that satisfy this selection, as well as n1 and h defined above? 3. under what conditions on n1 and n2, would the index be an efficient way of finding records satisfying the condition from part (2)?