Question

part a
how were the soviets able to block access to berlin?

Explanation:

After World War II, Berlin was split into four occupied zones, with the Soviet Union controlling the eastern zone and surrounding the entire city. In 1948, the Soviets blocked all road, rail, and water access routes that ran through their occupied eastern Germany to reach the western sectors of Berlin. This cut off supplies like food, fuel, and medicine to the western-held parts of the city.

Answer:

The Soviets controlled the territory surrounding Berlin (which was located deep within the Soviet-occupied zone of post-WWII Germany). In 1948, they closed all land, rail, and water access routes leading from western-occupied Germany into the western sectors of Berlin, completely cutting off ground supply lines to the city.