Use the net to find the surface area of the prism 5in 12in 13in and height is 8in

Area of Bottom Rectangle: 12 in X 8 in = 96 in^2

Area of Top Rectangle: 13 in X 8 in = 104 in^2

Area of Side Rectangle: 5 in X 8 in = 40 in^2

Area of Side Triangle: (5 in X 12 in) / 2 = (60) / 2 = 30 in^2

So total surface area = 96 + 104 + 40 + 2 (30) = 300 in^2