The surface area of a rectangular prism is 2 times the area of the bases + the perimeter x the height. Given the information above, all we have to do is substitute it into the formula.
SA = 2B + ph
SA = 2(8x3) + 2(8+3) x 13
SA = 48 + 26 x 11
SA = 48 + 286
SA = 334