the positive integer k has exactly two positive prime factors

the positive integer k has exactly two positive prime factors, 3 and 7. If K has a total of 6 positive factors, including 1 and k, what is the value of K?
1) 3^2 is a factor of k
2) 7^2 is NOT a factor of k


SHORTCUT METHOD:if you know the following useful fact, then you can solve this problem much more quickly.USEFUL FACT: if a, b, ... are the EXPONENTS in the prime factorization of a number, then the total number of factors of that number is the product of (a + 1), (b + 1), ...example:540 = (2^2)(3^3)(5^1), in which the exponents are 2, 3, and 1. therefore, 540 has (2 + 1)(3 + 1)(1 + 1) = 3 x 4 x 2 = 24 different factors.
with this shortcut method, realize that 6 (the total number of factors) is 3 x 2. therefore, the exponents in the prime factorization must be 2 and 1, in some order.therefore, there are only two possibilities: k = (3^2)(7^1) = 63, or k = (3^1)(7^2) = 147.
statement (1) includes 63 but rules out 149, so, sufficient.

statement (2) includes 63 but rules out 149, so, sufficient.answer = (d).