Because sandpaper is an abrasive and will leave minute scratches. Any surface damage from scratches could lead to rust.
Such hard abrasion will scratch the metal surface. This will make future cleaning more difficult as staining will get inside the scratches and be difficult to remove.
It is not advisable to attempt cleaning the inside of an LCD TV screen at home. It should be brought to a professional. If you are going to attempt it, the entire back of the TV will need to be removed.
You can but it is not advisable.
both, on the outside it's aluminum oxide but the inside is just aluminum
Yes.
the air inside the can keeps it afloat
Yes.
Because of energy and the different components
radiation
It's hard because of the chemicals that are inside of it. Though aluminum foil is not so hard it's still made out of aluminum.
A circle labeled "metal" with a smaller circle labeled "aluminum" completely inside it
Don't use aluminum wire inside the house.