We have a rectangular prism.
The surface area is the sum of the area of the faces.
We have 3 pairs of faces. Each pair has two pair of measures for the sides, so, if the sides are a=12, b=12 and c=25, we can calculate the surface area as:
[tex]\begin{gathered} S=2\cdot a\cdot b+2\cdot a\cdot c+2\cdot b\cdot c \\ S=2\cdot12\cdot12+2\cdot12\cdot25+2\cdot12\cdot25 \\ S=2\cdot144+2\cdot300+2\cdot300 \\ S=288+600+600 \\ S=1488in^2 \end{gathered}[/tex]Answer: the surface area is 1488 square inches.
NOTE: if we want the surface in square feet we can do:
[tex]S=1488in^2\cdot(\frac{1ft}{12in})^2=1488in^2\cdot\frac{1ft^2}{144in^2}\approx10.33ft^2[/tex]The surface area is approximately 10.33 square feet.