Which set of expressions are not equivalent?

(9 c + 12) - c - 3 and 8 c + 9
4 c - 2 c - 3 and 2 c - 3
5 c - 2 c + 8 - 4 and 3 c + 4
0.5 + (10 c + 8) and 5 c - 4