There are four sketches below. the first sketch shows a sample of substance x. the three sketches underneath it show three different changes to the sample. you must decide whether each of these changes is possible. if a change is possible, you must also decide whether it is a physical change or a chemical change. each sketch is drawn as if the sample were under a microscope so powerful that individual atoms could be seen. also, you should assume that you can see the entire sample, and that the sample is in a sealed box, so that no matter can enter or leave.