I'm not entirely sure but I think this is how you solve it:
surface area is basically just the area of the of surface, so the rectangular prism has 6 sides, surfaces, areas, with different lengths, and you need to find the area of the different areas, so first, the top and bottom, (3 by 10) so that would be 60, then, the two wide sides, (20 by 10) so that would be 400, and then lastly the two thin sides, which is 3 by 20, so that would be 120, now you add all the stuff together, 60 plus 120 plus 400 which is 580, so the surface area would be 580 all around. I hope this made sense. :// goodluck
