Question

the set of natural numbers is a subset of the set of integers
true or false

Answer 1

True. The set of natural numbers includes all positive whole numbers (1, 2, 3, ...) and the set of integers includes all whole numbers, including both positive and negative numbers (..., -3, -2, -1, 0, 1, 2, 3, ...). So, every natural number is also an integer.