7.both slicing an apple and a chemical change such as cooking an egg cannot be reversed. however, why is slicing an apple still considered only a physical change?

In order, consider a change as chemical change, the change must produce a new product. If the change doesn't produces a new product it is considered as physical change.

As far as the given concept, slicing of apple is not considered as chemical change because in this activity a new product is not formed and apart from this once an apple is sliced it cannot be reversed into a full apple again. Due to all these reason, slicing of apple is considered as physical change.

the bullets go in this order.

4, 1, 3, 5, 2

answer; i believe the correct answer is ( proteins );