Can anyone help me out with this? it is Algebra 1

1. -9n -n -3m



2. 3ab -2ac +4ab



3. 2a -4b +3ab -5a +2b



4. 8x -9y -3xy - 2y -x +4xy



5. 2r -3s -t +3t +3s

Simplify each expression to lowest terms. Remember, not all of your answers will simplify completely!