Match each innovation to the best impact it had on WWI. Tanks
Broke the stalemate of trench warfare
Planes
Led to a stalemate on the Western Front
Submarines
Used by Germans to sink ships in the Atlantic
Trench Warfare
Led to massive amounts of casualties
Machine Guns
Used for reconnaissance and spying

tanks-Broke the stalemate of trench warfare

planes-Used for reconnaissance and spying

submarines-Used by Germans to sink ships in the Atlantic

Trench Warfare-Led to a stalemate on the Western Front

Machine Guns-Led to massive amounts of casualties

Explanation:

might be agreeing to participate ethically with other european nations in the slave trade

or notifying other european nations when taking possession   of african territories