Respuesta :

assuming the lid sits on top of the box and that's it

ok, so then we gots
10+30=40

length is 60
width is 45
height is 40


SA=2(LW+LH+WH)
SA=2(60*45+60*40+45*40)
SA=2(2700+2400+1800)
SA=2(6900)
SA=13800 square cm