First we need to convert 1 ft to inches
1ft= 12 in
We will use the formula of surface area
[tex]SA=2lw+2lh+2wh[/tex]
where l is the length, w is the width and h is the height
In our case
l=12 in
w=8in
h=6 in
we substitute
[tex]SA=2(12)(8)+2(12)(6)+2(8)(6)[/tex]
we simplify
[tex]SA=432\text{ in}^2[/tex]
She needs 432 square inches
