求助2道题，谢谢

This year Henry will save a certain amount of his income, and he will spend the rest.  Next year Henry will have no income, b.  In terms of r, what fraction of his income should Henry save this year so that next year the amount he was available to spend will be equal to half the amount that he spends this year?

 A. 1/(r+2)

 B. 1/(2R+2)

 C. 1/(3r+2)

D. 1/(r+3)

E. 1/(2r+3)

为啥选E，谢谢

2.

What is the sum of a certain pair of consecutive odd integers?

(1)     At least one of the integers is negative.

(2)     At least one of the integers is positive.

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.

如何理解 a certain pair of consecutive odd integers 这个概念？  3，－3 算是一对连续的奇整数吗？

What is the sum of a certain pair of consecutive odd integers?

(1)     At least one of the integers is negative.

(2)     At least one of the integers is positive.

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.

如何理解 a certain pair of consecutive odd integers 这个概念？  3，－3 算是一对连续的奇整数吗？