单选题 State X has a sales tax rate of k percent on all purchases and State Y has a sales tax rate of n percent on all purchases. What is the value of k - n ?(1) The sales tax on a $15 purchase is 30 cents more in State X than in State Y. (2) The sales tax rate in State X is 1. 4 times the sales tax rate in State Y.

A、 Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
B、 Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C、 BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
D、 EACH statement ALONE is sufficient.
E、 Statements (1) and (2) TOGETHER are NOT sufficient.

【正确答案】 A

【答案解析】(1) It is given that l5(k/100)=15(n/100) + 0.30.It follows that 15(k -n) = 30, from which the value of k-n can be determined; SUFFICIENT.(2) It is given that k = 1.4n, from which k- n cannot be determined. For example, if n =5, then k = 7 and k- n=2. However, if n = 10, then k = 14 and k - n = 4; NOT sufficient.The correct answer is A; statement 1 alone is sufficient.