Answer:
424
Explanation:
To find the surface area, you need to find the area of all the faces of the shape. Because this is a rectangle, you only need to find the 3 different faces and then multiply them by 2. For the largest face, the dimensions are 8*15, which is 120. Multiply that by 2 and you get 240. For the long, slim face, the dimensions are 4*15, which is 60. Multiply that by 2 and you get 120. Finally, the smallest face's dimensions is 8*4, which is 32. Double that and you get 64. Now all you need to do is add all the products up. 240+120+64 is 424, which is your answer.
Hope this helped!