Can anyone help me with this Advanced Multivariable Calculus

Can anyone help me with this Advanced Multivariable Calculus question?

Problem 3: Suppose that k is a positive number. Suppose that K is a number collection such that for any number in K, there is another number in K, such that the difference between these two numbers is less than k. Must K have a limit point? Explain your answer using English sentences.

Solution

Let k be a positive number,

K is a number collection for any number in K.

consider there is n number of collection of K numbers ,can be written as nK² ,

The difference between nK² - K< k

K must have a limit point since{ According to the definition of limit point we have for any set K is a point which has points of K other than itself close to it.}