How many pounds is this 920mmx70kg?

Answer 1

This question cannot be answered.

A pound is a measure of mass and so has dimensions [M].

A kilogram is a measure of mass and so has dimensions [M].

A millimetre is a measure of distance and so has dimensions [L].

So a mm * kg has dimensions [ML].

There is a mismatch in dimensions between pounds and mm*kg which means that any conversion between the two is not valid.