1. **State the problem:** We need to find the surface area of a rectangular prism with dimensions 10 m, 10 m, and 15 m. 2. **Formula for surface area of a rectangular prism:** $$SA = 2(lw + lh + wh)$$ where $l$, $w$, and $h$ are the length, width, and height respectively. 3. **Substitute the given values:** $$l = 10, w = 10, h = 15$$ 4. **Calculate each product:** $$lw = 10 \times 10 = 100$$ $$lh = 10 \times 15 = 150$$ $$wh = 10 \times 15 = 150$$ 5. **Sum the products:** $$100 + 150 + 150 = 400$$ 6. **Multiply by 2:** $$SA = 2 \times 400 = 800$$ 7. **Final answer:** The surface area of the rectangular prism is $$800\text{ m}^2$$.