Answer:
You can see 2-D flat shapes on the faces of 3-D objects.
For example: You go to the store and you see a box,
the box has 6 faces. The bottom of the box is one of It's faces which is 2-D.
Step-by-step explanation:
I think the answer would be 5
So it must have side length √16 = 4 cm and diagonal length 4√2 cm.
