Well on a table of data, if the y coordinates increase a lot over a short x distance then it will be steep.
In an equation, you would put it into y = mx + b form and whatever your m is will be your slope. If m is large, it will be steep.
I see no reason for the aluminum foil to have lost any volume, matter, mass , etc.
If all pieces are retrieved for measuring. - &
If a clean cut was achieved- and the blade used to cut did not impede upon the proceedings by also being variable, then I reiterate that there should be no difference in volume, matter, mass, etc.
