suppose n is an integer. select all statements below that are true:
1) n^2 + n is always an even integer
2) n^2 + n is always an even integer when n is even
3) n^2 + n is always an even integer when n is odd
4) n^2 + n is never an even integer when n is odd
5) n^2 + n is never an even integer
6) n^2 + n is sometimes an even intege
1) n^2 + n is always an even integer
2) n^2 + n is always an even integer when n is even
3) n^2 + n is always an even integer when n is odd
4) n^2 + n is never an even integer when n is odd
5) n^2 + n is never an even integer
6) n^2 + n is sometimes an even intege