Just about every airplane flown by any nation in World War II was a propeller-driven plane. The Germans fielded the first operational jet fighter, the Messerschmitt Me 262, but it only saw partial action in World War II because it was transported late in the war and underwent from some engine issues. Here were other jet aircraft before the Me-262, but it was the first one to be delivered to the troops and used in combat operations. The first jet aircraft was the German HE 178, followed by Italian and British jets (N1 and Gloster E.28 respectively).
Renaissance is a French word meaning “rebirth.” It refers to a period in European civilization that was marked by a revival of Classical learning and wisdom.
Spain's motivation to help the American colonists was driven by a desire to regain the land it had lost to Britain and, with other European powers, make incremental gains against British possessions in other parts of the world.
The USA developed the more powerful H-Bomb because it would be more powerful than the atomic bomb and it wold give the USA advantage over Russia and their nuclear bombs.