Detailed Instructions: In this task, you're given a context, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both context and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the context or linked information.
Q: Context: which the 1943 Quebec Agreement merged with the American Manhattan Project Link Information: Lord Cherwell had taken the matter to the Prime Minister, Winston Churchill, who became the first national leader to approve a nuclear weapons programme on 30 August 1941 Answer: 2
A:
How long had the secret project, Tube Alloys, been going on before it merged with the American Manhattan Project according to the Quebec Agreement?