Based on the answers provided, here are the corrections needed for the 3D object:

1. Ensure that the surface area of the square on the left is 75% smaller than the square on the right. This will clarify the size difference between the two squares.

2. Make sure that the larger square is extruded twice as much as the smaller square. This will help to differentiate the two squares not only by their surface area but also by their extrusion.