Final answer:
The Manhattan Project was a research project that developed the atomic bomb during World War II.
Step-by-step explanation:
The Manhattan Project was NOT the codename for the invasion of Japan. The Manhattan Project was actually a research project that resulted in the development of the atomic bomb during World War II. It was carried out by the United States with the goal of creating a powerful weapon to end the war. The project was top secret and took place from 1939 to 1946, involving thousands of scientists and engineers.
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