[b]1.[/b] Move the slider so that the line l is parallel to the plane 3x - y + z = 3;[br][b]2.[/b] Click to see the normal vector to the plane 3x - y + z = 3;[br][b]3.[/b] Click to see the parallel plane containing the line l;[br][b]4.[/b] Click to see the distance;[br][b]5.[/b] Use "Rotate 3D Graphics View" to view from different angles.