Lead is much heavier than stainless steel.
Depends, of course, on the density of the steel.
A steel plate of that size would weigh approximately 368 pounds.
If it is 20 gage steel it would weigh about 450 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.
A 1 inch cube made of high-density material like steel or lead would weigh approximately 0.3 pounds (4.8 ounces). However, if the material is low-density like balsa wood or foam, it would weigh significantly less.
86959459 lbs
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 12x12x1 piece of mild steel weighs approximately 40.8 pounds.