Steel pipe varies in weight according to size and thickness (schedule).
About 7000 lbs Source: 30 seconds of google search
You need to specify the wall thickness in order to calculate the weight.
Not much.
15000
Depends, of course, on the density of the steel.
If it is 20 gage steel it would weigh about 450 pounds
A steel plate of that size would weigh approximately 368 pounds.
2lbs
490 lb/ft^3
That will depend on the capacity of the tank and the gauge of the steel used to make it.
50 or 60 lbs.
You cannot weigh an area, but you can weigh a volume... so, one cubic meter of stainless steel weighs 7480 - 8000 kg. See related link for the source.
A 1-foot cube of steel weighs approximately 490 pounds.
A 12x12x1 piece of mild steel weighs approximately 40.8 pounds.
roughly 3.09996 pounds/SF
the 16 inch steel rim is about 9.4kg