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If r and s are positive integers, is r/s an integer?

(1) Every factor of s is also a factor of r.
(2) Every prime factor of s is also a prime factor of r.

Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.

Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.

BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.

EACH statement ALONE is sufficient.

Statements (1) and (2) TOGETHER are NOT sufficient

RichardVeritas

我选A

1）sufficient.
S is a factor for itself, so s is a factor of r.  r/s is integer.

2) not sufficient
E.g. s = 35*5.  factors 5, 7.  r = 35.  Factors 5,6 each is a prime factor of r.