Problem Solving
试题详情
题目：
S is a set of integers such that
I) If x is in S, then –x is in S.
II) If both x and y are in S, then so is x + y.
Is –2 in S?
(1) 1 is in S.
(2) 0 is in S.
(2) 0 is in S.
选项:
A、A. if statement (1) ALONE is sufficient to answer the question but statement (2) alone is not sufficient;
B、B. if statement (2) ALONE is sufficient to answer the question but statement (1) alone is not sufficient;
C、C. if the two statements TAKEN TOGETHER are sufficient to answer the question, but NEITHER statement ALONE is sufficient;
D、D. if EACH statement ALONE is sufficient to answer the question;
E、E. if the two statements TAKEN TOGETHER are still NOT sufficient to answer the question.
答案:
A
