How much work is done when a 4.0 newton box is carried horizontally a distance of 2.0 meters at a constant velocity?

If the box ended up at the same height above the floor as it started, then

no gravitational potential energy was added to the box in the form of work.

It doesn't even matter if the box moved up or down on the way.

Of course, work is done, and calories are expended. That's only because

your body is not 100% efficient, and it takes work to move arm and leg

muscles, walk, breathe, etc. But no work is done on the box as it moves

horizontally.