Where did the schleffen plan call for german troops to fight

Which of the following statements is true about the treaty of versailles ?

The internal combustion engine was an innovation of

23. how does specialization among nations encourage interdependence? nations work together to share labor and resources to produce vital goods. nations sign treaties prohibiting taxes on imports. nations produce specific goods and then trade to obtain things they need. nations that are more developed agree to fund development in nations with limited industry.