A 4.22 kg briefcase is sitting at rest on a level floor. what is its weight in newtons

The briefcase weighs 41.4 Newtons. It doesn't matter whether the briefcase is at rest or excited or on the floor or on the table or under water or floating in chicken soup or hanging from the end of a string or dropping from an airplane. If it's anywhere near the Earth its weight is 41.4 Newtons.

The answer is 41.384063 Newtons or 41.38 if simplified.