Question: Given the below context:  At Birmingham, Oliphant's team had reached a different conclusion. Oliphant had delegated the task to two German refugee scientists, Rudolf Peierls and Otto Frisch, who could not work on Oliphant's radar project because they were enemy aliens and therefore lacked the necessary security clearance. Francis Perrin had calculated the critical mass of uranium to be about 40 tonnes (39 long tons; 44 short tons). He reckoned that if a neutron reflector were placed around it, this might be reduced to 12 tonnes (12 long tons; 13 short tons). Peierls attempted to simplify the problem by using the fast neutrons produced by fission, thus omitting consideration of moderator. He too calculated the critical mass of a sphere of uranium in a theoretical paper written in 1939 to be "of the order of tons".Peierls knew the importance of the size of the critical mass that would allow a chain reaction to take place and its practical significance. In the interior of a critical mass sphere, neutrons are spontaneously produced by the fissionable material. A very small portion of these neutrons are colliding with other nuclei, while a larger portion of the neutrons are escaping through the surface of the sphere. Peierls calculated the equilibrium of the system, where the number of neutrons being produced equalled the number escaping.Niels Bohr had theorised that the rare uranium-235 isotope, which makes up only about 0.7% of natural uranium, was primarily responsible for fission with fast neutrons, although this was not yet universally accepted. Frisch and Peierls were thus able to revise their initial estimate of critical mass needed for nuclear fission in uranium to be substantially less than previously assumed. They estimated a metallic sphere of uranium-235 with a radius of 2.1 centimetres (0.83 in) could suffice. This amount represented approximately 1 kilogram (2.2 lb) of uranium-235. These results led to the Frisch–Peierls memorandum, which was the initial step in the development of the nuclear arms programme in Britain. This...  Guess a valid title for it!
Answer: Tube Alloys

Question: Given the below context:  After a row, Ellinor Devine reveals to her husband Sir Richard that he is not actually the father of their son, also named Richard, but that he was fathered by her cousin, Lord Bellasis. Sir Richard throws his son out and storms off in a rage. Shortly afterwards, Richard Junior finds his biological father dead in the forest. Only the viewer and an unidentified witness know that Lord Bellasis has actually been killed by his own son, known as John Rex. However, it is Richard Devine who is found next to the body and arrested. Thinking that his father killed Bellasis, Richard wants to protect his mother's reputation and gives his name as Rufus Dawes. The convict ship that brings Dawes to Tasmania also carries the new governor Vickers and his wife and his daughter Sylvia. The commander of the ship is a brutal man by the name of Maurice Frere. With the Vickers is a young girl, Sarah Purfoy, as a nurse to the child. However, she really is the fiancée of John Rex, convicted for forgery, and tries to help the convicts take the ship. The rebellion is led by a murderer named Gabbett. They fail when Dawes overhears their plans and manages to warn an officer while being brought to a quarantine room for the sick. Gabbett decides to claim that Dawes was the actual ringleader.  Guess a valid title for it!
Answer: For the Term of His Natural Life (1927 film)

Question: Given the below context:  In 1942, Nazi Germany attempts to bring neutral Turkey into the war on its side by staging an assassination attempt on Franz von Papen, its own ambassador to the country. Much to the annoyance of Colonel Robinson, von Papen survives and the Russians that his agent provocateur was trying to frame have solid alibis, forcing him to turn to another scheme to inflame Turkey's traditional rivalry with Russia.  Meanwhile, American machinery salesman Joe Barton boards the Baghdad-Istanbul Express train at Aleppo and is attracted to another passenger, Ana Remzi. She is worried about being searched by customs agents once they reach the Turkish border; she asks Joe to hold on to an envelope containing some securities, all that remains of her inheritance. Joe obliges, but when he later examines the envelope, he finds maps of Turkey with writing on them. When they stop in Ankara, he goes to her hotel to return her property, only to find she has been fatally wounded. He hides when someone else approaches the room. He watches unobserved as Soviet spy Nikolai Zaleshoff searches the dead woman's luggage. Then, Joe exits through the window. Leaving the scene, he is seen by Tamara Zaleshoff, Nikolai's sister and partner in espionage. The Turkish police take Joe in for questioning, only it turns out that they are German agents. They take him to their leader, Colonel Robinson. Robinson wants the maps. Joe refuses to cooperate, and is taken away to be interrogated by Mailler. Before the Germans get very far, Joe is rescued by Nikolai. When the Zaleshoffs reveal that they are Soviet agents, Joe agrees to fetch them the documents. Unfortunately, he finds his hotel room has been ransacked and the documents stolen. Joe, it turns out, is also a spy (for the United States). When he reports to his boss, McNamara, he is assigned an assistant, Hassan.  Guess a valid title for it!
Answer:
Background to Danger