Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Input: Consider Input: Three many families are known quarks divided into.

Output: How many families are known quarks divided into?


Input: Consider Input: Breast cancer is the most common type of cancer in adult females.

Output: What is the most common type of cancer in adult females?


Input: Consider Input: The long-lived isotopes require thousands of years to decay to a safe level in a nuclear reactor.


Output: How long do the long-lived isotopes require to decay to a safe level in a nuclear reactor?