Problem: Please answer a question about the following article about Gramophone record:
Over time, fidelity, dynamic and noise levels improved to the point that it was harder to tell the difference between a live performance in the studio and the recorded version. This was especially true after the invention of the variable reluctance magnetic pickup cartridge by General Electric in the 1940s when high quality cuts were played on well-designed audio systems. The Capehart radio/phonographs of the era with large diameter electrodynamic loudspeakers, though not ideal, demonstrated this quite well with "home recordings" readily available in the music stores for the public to buy.
In what era could you find good quality recordings and playbacks at home?
A: 1940s


Question: Read this and answer the question

Hunting and gathering was presumably the subsistence strategy employed by human societies beginning some 1.8 million years ago, by Homo erectus, and from its appearance some 0.2 million years ago by Homo sapiens. It remained the only mode of subsistence until the end of the Mesolithic period some 10,000 years ago, and after this was replaced only gradually with the spread of the Neolithic Revolution.

When did Homo sapiens begin using subsistence gathering?
Answer: 0.2 million years ago


Problem: In 1864, Andrew Johnson (a War Democrat from Tennessee) was elected Vice President under Abraham Lincoln. He became President after Lincoln's assassination in 1865. Under Johnson's lenient re-admission policy, Tennessee was the first of the seceding states to have its elected members readmitted to the U.S. Congress, on July 24, 1866. Because Tennessee had ratified the Fourteenth Amendment, it was the only one of the formerly secessionist states that did not have a military governor during the Reconstruction period.
Their ratification of which Amendment spared Tennessee a military governor during Reconstruction?
The answer is the following: Fourteenth


Complex serological techniques have been developed into what are known as Immunoassays. Immunoassays can use the basic antibody – antigen binding as the basis to produce an electro - magnetic or particle radiation signal, which can be detected by some form of instrumentation. Signal of unknowns can be compared to that of standards allowing quantitation of the target antigen. To aid in the diagnosis of infectious diseases, immunoassays can detect or measure antigens from either infectious agents or proteins generated by an infected organism in response to a foreign agent. For example, immunoassay A may detect the presence of a surface protein from a virus particle. Immunoassay B on the other hand may detect or measure antibodies produced by an organism's immune system that are made to neutralize and allow the destruction of the virus.
What are immunoassays?
Complex serological techniques


Input: Kanye West
At a December 2008 press conference in New Zealand, West spoke about his mother's death for the first time. "It was like losing an arm and a leg and trying to walk through that", he told reporters.

Where did Kanye West first speak about his mother's death?
Output: New Zealand


Problem: Please answer a question about the following article about Antarctica:
Since the 1970s, an important focus of study has been the ozone layer in the atmosphere above Antarctica. In 1985, three British scientists working on data they had gathered at Halley Station on the Brunt Ice Shelf discovered the existence of a hole in this layer. It was eventually determined that the destruction of the ozone was caused by chlorofluorocarbons (CFCs) emitted by human products. With the ban of CFCs in the Montreal Protocol of 1989, climate projections indicate that the ozone layer will return to 1980 levels between 2050 and 2070.
What chemical was discovered to have caused the hole in the ozone?
A:
chlorofluorocarbons