Based on the answers provided, the following corrections need to be made to the 3D object:

1. Change the base shape of the object from a hexagon to a square. This will address the issue identified in the first question, where the object was not square in shape. 

2. No changes are needed regarding the extrusion as it is already correct.

3. Once the base is a square, ensure that the length of the extrusion is twice the length of the square's side. This will make the answer to the third question clear and affirmative.