Question 828922
The box is 7 x 4 x 5
Think of it as a 7 x 4 rectangle
laying flat on a table. with a 
height of 5.
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There are (2) 7 x 4 surfaces
There are (2) 7 x 5 surfaces
There are (2) 4 x 5 surfaces
That is {{{ 3*2 = 6 }}} surfaces total
{{{ 2*( 7*4 + 7*5 + 4*5 ) = 2*( 28 + 35 + 20 ) }}}
{{{ 2*83 = 166 }}} square units
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The volume is {{{ 7*4*5 = 140 }}} cubic units