Here is how to get the Surface Area of a triangular prism.
First you must find their areas first then multiply it by 2 (because it has 2 faces) except for the base, since it has a triangular base.
A = bxh/2 A = 15 m x 30 m A = 30 m x 18 m
= (18 m x 12 m )/2 = 450 m^2 = 540 m^2
= 216 m ^2/2
= 108 m^2
Add all the faces:
SA = 2 (108 m^2) + 2 (540 m^2 ) + 450 m^2
= 216 m^2 +1080 m^2 + 450 m^2
= 1,746 m^2
The answer is not found in your choices. The attached picture is also showing m (meter) as the unit used not cm.....so I guess you got the wrong choices.