Triangle is 1/2 x base x height so it would be 1/2 x 10 x 12 which is 1/2 of 120 which is 60.
There are two triangle faces on each end so 60+60 = 120.
The area of a rectangle is length x width so 14 x 13 = 182.
There will be 3 rectangular faces as it is a triangular prism.
So 182 x 3 = 546.
Take 120 from the triangles and 546 from the rectangles.
120 + 546 = 666 cm2