Find the area of the triangle, then the area of the rectangular sides:
Area = 1/2 x 6 x 4 = 12 square yds.
There are two triangles ( front and back) 12 + 12 = 24
One side = 11 x 5 = 55 sq yds.
There are two sides: 55 +55 = 110 sq. yds.
The bottom is 6 x 11 = 66 sq. yds.
Total surface area = 66 + 110 + 24 = 200 sq yds.