code: public static double rectangularPrismSurfaceArea(final double length, final double height, final double width) {
      return ((2 * length * height) + (2 * length * width) + (2 * height * width));
    }
docs: Calculates the surface area of a rectangular prism;
  
  @param length a double value indicating the length of the rectangular prism (x axis).
  @param height a double value indicating the height of the rectangular prism (y axis).
  @param width a double value indicating the width of the rectangular prism (z axis).
  @return the surface area of a rectangular prism given the length, height and width of the sides.