Question: During the first half of the 1920s, engineers at Western Electric, as well as independent inventors such as Orlando Marsh, developed technology for capturing sound with a microphone, amplifying it with vacuum tubes, then using the amplified signal to drive an electromagnetic recording head. Western Electric's innovations resulted in a greatly expanded and more even frequency response, creating a dramatically fuller, clearer and more natural-sounding recording. Distant or less strong sounds that were impossible to record by the old methods could now be captured. Volume was now limited only by the groove spacing on the record and the limitations of the intended playback device. Victor and Columbia licensed the new electrical system from Western Electric and began issuing electrically recorded discs in 1925. The first classical recording was of Chopin impromptus and Schubert's Litanei by Alfred Cortot for Victor.
Try to answer this question if possible: What was an early took used to amplify sounds?
Answer: vacuum tubes
Question: Providing sufficient base drive current is a key problem in the use of bipolar transistors as switches. The transistor provides current gain, allowing a relatively large current in the collector to be switched by a much smaller current into the base terminal. The ratio of these currents varies depending on the type of transistor, and even for a particular type, varies depending on the collector current. In the example light-switch circuit shown, the resistor is chosen to provide enough base current to ensure the transistor will be saturated.
Try to answer this question if possible: What fluctuates the most in a transistor?
Answer: unanswerable
Question: Gladstone returned to power after the 1892 general election; he was 82 years old. Victoria objected when Gladstone proposed appointing the Radical MP Henry Labouchere to the Cabinet, so Gladstone agreed not to appoint him. In 1894, Gladstone retired and, without consulting the outgoing prime minister, Victoria appointed Lord Rosebery as prime minister. His government was weak, and the following year Lord Salisbury replaced him. Salisbury remained prime minister for the remainder of Victoria's reign.
Try to answer this question if possible: How old was Gladstone when he returned to power?
Answer: 82 years old
Question: Some countries were not included for various reasons, mainly the unavailability of certain crucial data. The following United Nations Member States were not included in the 2011 report: North Korea, Marshall Islands, Monaco, Nauru, San Marino, South Sudan, Somalia and Tuvalu.
Try to answer this question if possible: What is the main reason that countries were excluded from the 2011 report?
Answer:
unavailability of certain crucial data