Sam wrote these four expressions .
1 . n + n + n + n + 2
2 . n + n + n + 2
3 . 4n + 2
4 . 2n + 2n + 2n

part a- which expressions are equivalent? write your answer in the space provided .
part b- choose two of sam’s expressions that are not equivalent . explain how you know they are not equivalent . write your answer in the space provided .