Weight, mass & density

Kilograms and pounds, stone for the units a payload plate still uses, metric tonnes and US short tons; and the derived pairs that carry a shape with them — kilograms per cubic metre against pounds per cubic foot, per square metre against per square foot, per metre against per foot.

Which ton, and this one costs money rather than pride. A short ton is 907 kg and a metric tonne is 1,000, so a quote priced per ton and delivered per tonne is out by ten per cent across the whole load, which on aggregate is a truck. The pages name the two apart in their titles and never abbreviate either to the word on its own.

What a floor, a lintel or the ground underneath can carry, none of which follows from a weight alone.