What is the surface area of this design? Please show work!

Answer:
The answer is 392
Step-by-step explanation:
Divide the figure into two smaller shapes.
The area of the smaller rectangle:
4x6 + 4x6 + 4x6 + 4x4 + 4x4 = 104
Area of the bigger rectangle: (we do not count the sides that overlap between the figures as we are only finding the area of the SURFACE)
10x6 + 10x6 + 10x6 + 6x6 + 6x6 + 6x6 = 288
288 + 104 = 392