Respuesta :
since it is a box you need to do these calculations
2(7*13)
2(13*8)
2(8*7)
that is because for every side, there is one of the exact same dimensions across from it.
after adding those three separate answers together, you get
502 square mm
2(7*13)
2(13*8)
2(8*7)
that is because for every side, there is one of the exact same dimensions across from it.
after adding those three separate answers together, you get
502 square mm