Chapter 3.1, Problem 19ES

Consider the following statement:

$\forall$ integer n, if n²is even then n is even.

Which of the following are equivalent ways of expressing this statement?

1. All integer whose squares and are even.
2. Given any integer whose square is even, that integer is itself even.
3. For all integers, there are some whose square is even.
4. Any integer with an even square is even.
5. If the square of an integer is even, then that integer is even.
6. All even integers have even squares.