it is a net.
A projection. A net is the other way around: a 2-d pattern that can be folded into a 3-d shape.
A mathematical net is a flat object which can be folded and glued to make a 3-D object.
The net of a 2 dimensional shape can be folded into a 3 dimensional shape
Did It Myself ... With trampoline nets in place, they prevent someone from inside falling out ... Step 3 Make the Trampoline Enclosure ... DoItYourself.com, founded in 1995, is the leading independent home improvement and repair website.
Nowhere. Stop believing movies are real. Folding modern steel doesn't make it better, anyway. 16th-century steel sucked and it was folded to make it suck less.
4
It does not. The company folded after Tomba 2
Any 2-dimensional shape can be folded to form a 3-d shape. For example, any work of origami.
enclosure of a letter
It would help if there were more information on "this 3-D figure". In view of the available information, the only possible answer is "That one!"
A net is a two dimensional pattern that can be cut out and folded to make a 3-dimensional [solid] shape. A 2-dimensional shape, such as a square, does not have a net!