Finite Element Analysis (FEA): 3D Surface Normal Cross Product

In 3D CAD modeling and finite element stress analysis: Given three 3D vertices of a planar triangle: $A(x_1, y_1, z_1)$, $B(x_2, y_2, z_2)$, $C(x_3, y_3, z_3)$ in counter-clockwise order: Write a function that calculates the **unit normal vector** $\hat{n} = (n_x, n_y, n_z)$ perpendicular to the triangle surface using the cross product: $$\vec{u} = B - A, \quad \vec{v} = C - A$$ $$\vec{N} = \vec{u} \times \vec{v}$$ $$\hat{n} = \frac{\vec{N}}{\|\vec{N}\|}$$ Format each component to 1 decimal place (e.g., `0.0 0.0 1.0`). ### Input Format - Line 1: `Ax Ay Az` - Line 2: `Bx By Bz` - Line 3: `Cx Cy Cz` ### Output Format - Print three space-separated floats: `nx ny nz`, each formatted to 1 decimal place. ### Constraints - Vertices define a non-degenerate triangle (magnitude of cross product $> 0$).