We know that Natural Numbers are closed under addition (the sum of any two natural numbers is always a natural number). Are they closed under subtraction? Provide a couple of examples to justify your answer.

No, natural numbers are not closed under subtraction. If we subtract a larger natural number from a smaller one, we get a negative number, which is not a natural number.
Some examples are:
\(1 − 10 = −9\)
\(3 − 4 = −1\)
Even subtracting the smallest natural number(1) from itself gives us 0, which is not a natural number.
\(1 − 1 = 0\)