Answer: The total surface area is 2784 sq. inches.
Step-by-step explanation: We are given to find the total surface area of the given figure.
Let us divide the figure into two two cuboids 1 and 2 as shown in the attached figure.
We know that the surface area of a cuboid with length 'l', breadth 'b' and height 'h' is given by
[tex]S.A.=2(l_1b_1+l_1h_1+h_1b_1).[/tex]
The dimensions of the cuboid 1 are
[tex]length,~l_1=14~\textup{inches},\\\\breadth,~b_1=12~\textup{inches},\\\\height,~h_1=24-10=14~\textup{inches}.[/tex]
The dimensions of the cuboid 2 are
[tex]length,~l_2=30~\textup{inches},\\\\breadth,~b_1=14~\textup{inches},\\\\height,~h_1=10~\textup{inches}.[/tex]
Therefore, surface area of cuboid 1 is given by
[tex]S.A_1\\\\=2(l_1b_1+l_1h_1+h_1b_1)\\\\=2(14\times 12+14\times 14+14\times 12)\\\\=2(532)\\\\=1064~\textup{sq. inches.}[/tex]
And surface area of cuboid 2 is given by
[tex]S.A_2\\\\=2(l_2b_2+l_2h_2+h_2b_2)\\\\=2(30\times 14+30\times 10+14\times 10)\\\\=2(420+300+140)\\\\=2(860)\\\\=1720~\textup{sq. inches}.[/tex]
Thus, the total surface area of the figure is
[tex]S.A.=S.A_1+S.A_2=1064+1720=2784~\textup{sq. inches}.[/tex]
