1. If n and k are positive integers, is SQRT(n+k) > 2 SQRT(n)
(1) k > 3n
(2) n + k > 3n

2. Is the integer n a multiple of 15?
(1) n is a multiple of 20.
(2) n + 6 is a multiple of 3.

3. In a certain coding scheme, each word is encoded by replacing each letter in the word with another letter. The same code is used for all words, so that the same letter replaces a given letter each time the given letter occurs. What code will result when the word TAME is encoded by this scheme?
(1) When the word MAT is encoded, the result is DLX.
(2) When the word TEA is encoded, the result is XRL.

4. If d denotes a decimal, is d ≥ 0.5 ?
(1) When d is rounded to the nearest tenth, the result is 0.5.
(2) When d is rounded to the nearest integer, the result is 1.


My Answers are:

1. - E
2. - C
3. - C
4. - A

But I saw some differents answers for these question.