Final answer:
The United States responded to the Berlin blockade by implementing the Berlin Airlift, supplying the city by air for nearly a year. The blockade ended in May 1949, and the Western Allies formed West Germany.
Step-by-step explanation:
The United States responded to the Berlin blockade by implementing the Berlin Airlift. They, along with the United Kingdom, supplied the besieged city of Berlin by air for nearly a year. This extensive operation involved a British or U.S. plane taking off from Berlin's Tempelhof Airport every forty-five seconds. The Soviets ended the blockade in May 1949, and two weeks later, the Western Allies unified their occupation zones to form West Germany.
Learn more about Berlin blockade