They have a positive charge. All metals form positive ions.
The clue is " OVER THE TOP OF" metal sinks windows metal roof flashing metal beams The only possible answer is OVER THE TOP OF WINDOWS
No there metal not plastic the top has plastic
No, it is not safe to place metal on top of a microwave as it can cause sparks, fires, and damage to the microwave. Metal reflects the microwaves and can create a dangerous situation.
Ions
gold
Here's an article that suggests the top five metal ETFs: http://www.metaletfs.com/2009/10/18/the-top-metal-etfs-revealed/ . Note that this is just an opinion, so do your due dilligence.
Aluminium is used in top level metallization.
America's Top 10 - 1980 Top 10 Heavy Metal Bands of the 80's was released on: USA: 1989
metal
Aluminum
One answer to that is that you can have labels or headings at the top of columns or start of rows or beside particular figures as a way of identifying them. You could also mean the cell references that identify where the data is.
you just multiply top with top, bottom with bottom