You have to buy the size it comes in. As mentioned you can pay to have it cut.
Depends on what metal you are planning on buying. They will cut most things down for an additional charge but they do stock some pieces of sheet metal and what not inside that are smaller lengths. They also have a remnant section outside they sell by the pound but its a hit and miss when they have What you can use.
Sometimes it depends on the type of material you need. They also has a odds and ends section out front in the parking lot that has different pieces that might work at a discounted price.
Probably all 10, unless they have a scrap pile.
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