<PRE><B>Question 807435</B>
note that a 2 cm thickness implies that the outside dimensions for the box are
84 cm, 64 cm, 94 cm, therefore
a) volume of wood used (V) = (84*64*94) - (80*60*90)
   V = 505344 - 432000 = 73344 cubic cm
b) note that by convention length = 80 cm, width = 60 cm and height = 90 cm 
weight of metal sheeting (W) = the area of the six internal faces * 2
W = ((2*(80*60)) + (2*(60*90)) +(2*(80*90))) * 2
W = (9600 + 10800 + 14400) * 2
W = 69600 grams
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