Problem Solving
试题详情
题目：
For any positive integer n, the length of n is defined as the number of prime factors whose product is n. For example, the length of 75 is 3, since 75 = 3 × 5 × 5. How many two-digit positive integers have length 6 ?
选项:
A、None
B、One
C、Two
D、Three
E、Four
答案:
C
