What is the net force on an object that is being pushed and pulled with forces of 30N east, 21N north, 16N west and 21N south?

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.

Idon't know hope someone you