1)40,000 men served the U-Boats but 30,000 never returned.
2)For each man killed on battle, four others were wounded.
3)Hitler executed 84 of his generals, for various reasons.
4)From 1939 till the end of the war, the Allies dropped 3.4 million tons of bomb, mostly in industrial German cities.
5) The only nation that Germany declared war on was the U.S.