What were the results of the air war and the battle of the atlantic?

The battle of Atlantic took place in the northern region of the Atlantic Ocean, It spread to the US and Caribbean sea after US entered the war. The battle lasted for 5 years and three months. Initially, the Germans had the advantage as more German submarines patrolled  the Atlantic Ocean. The allies tried to counter the submarines by traveling in convoys and using destroyer ships to escort them. but this method proved to be ineffective. By the middle of 1943, the battle turned in the favor of Allies as German secret code were broken by the Allies and new underwater bombs were invented. Also, the United States' help in shipping supplies of soldiers and weapons needed for the invasion of Normandy was an important factor. The control of Atlantic changed the outcome as it kept Britain supplied and prevented the Germans from winning Europe.

b. the 200th birthday of the united states