Answer:
C. 864 unitsĀ²
Explanation:
We have the square in the base and four triangles on the lateral surface.
The formula of an area of a square:
![A_(\square)=a^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/hvivll16qv9e5mlcxb5y3fh9xe3o6ifttv.png)
a - side lenght
We have a = 16. Substitute:
![A_(\square)=16^2=256](https://img.qammunity.org/2020/formulas/mathematics/high-school/fgpc557yyrjmv2cr83glpe8te0sbwfuw1f.png)
The formula of an area of a triangle:
![A_(\triangle)=(bh)/(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/lno52qj68fpsap4rgzsubjkjy7w4juz781.png)
b - base
h - height
We have b = 16 and h = 19. Substitute:
![A_(\triangle)=((16)(19))/(2)=152](https://img.qammunity.org/2020/formulas/mathematics/high-school/10037unouan77wwq7k7dldvv32xy5xs04k.png)
The Surface Area:
![S.A.=A_(\square)+4_(\triangle)](https://img.qammunity.org/2020/formulas/mathematics/high-school/la7z5h2sl02fzdar64vql6ncid58n2vkdf.png)
Substitute:
![S.A.=256+4(152)=256+608=864](https://img.qammunity.org/2020/formulas/mathematics/high-school/cr5xml37xnli2oyy677uwr3zss6vd5gzei.png)