text: Your question isn't clear about the height of the prism; is the height 12 meters?\n\nThe base is a 3-4-5 right triangle (because 3^2 + 4^2 = 25, and sqrt(25) = 5), so the base perimeter is 3+4+5 = 12 meters, and the area of the base is 3*4/2 = 6 square meters.\n\nAssuming the height is 12 meters, the surface area is 12*12 + 2*6 = 156 square meters.