What will a UPS be used for in a building?
Answer: A
A UPS provides power to essential equipment when the mains fails.
An uninterruptible power supply holds a battery and an inverter, and switches over within milliseconds, so servers and medical equipment keep running long enough to be shut down safely or for a generator to start.
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Who co-founded Hotmail in 1996 and then sold the company to Microsoft?
Answer: C
Sabeer Bhatia co-founded Hotmail with Jack Smith in 1996, and sold it to Microsoft the following year for about $400 million.
Hotmail was among the first web-based email services, accessible from any browser rather than tied to an internet provider.
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'.TXT' extension refers usually to what kind of file?
Answer: A
A .TXT file is a plain text file.
It contains characters only, with no formatting, fonts or images, so it can be opened by any program on any system. That universality is why configuration files and program source are kept in it.
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What was the first ARPANET message?
Answer: A
The first ARPANET message was 'lo'.
On 29 October 1969 a team at UCLA began typing LOGIN to a machine at Stanford; the system crashed after the first two letters. The word LOGIN was completed about an hour later.
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Who built the world's first binary digit computer: Z1?
Answer: A
Konrad Zuse built the Z1, the first binary programmable computer, in his parents' living room in Berlin between 1936 and 1938.
It was mechanical, used binary floating-point arithmetic and read its program from punched film. It was destroyed in an air raid in 1943.
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What is the term to ask the computer to put information in order numerically or alphabetically?
Answer: D
Putting information in numerical or alphabetical order is sorting.
Every spreadsheet and database offers it, ascending or descending, on one field or several. The efficiency of sorting algorithms is one of the classic subjects of computer science.
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In what year was the "@" chosen for its use in e-mail addresses?
Answer: B
The @ sign was chosen for email addresses in 1972.
Ray Tomlinson picked it because it appeared on the keyboard, was not used in names, and read naturally as 'user at host'. He had sent the first network email the year before.
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What frequency range is the High Frequency band?
Answer: D
The High Frequency band runs from 3 to 30 MHz.
HF waves are reflected by the ionosphere, so they can travel thousands of kilometres by skywave, which is why short-wave broadcasting, amateur radio and long-range aviation use the band.
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What do we call a collection of two or more computers that are located within a limited distance of each other and that are connected to each other directly or indirectly?
Answer: C
Computers within a limited distance, connected to each other, form a local area network.
A LAN covers a building or campus and is owned by one organisation. A WAN spans a much greater distance and usually uses leased lines or public networks between its sites.
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Once the active medium is excited, the first photons of light are produced by which physical process?
Answer: B
The first photons in a laser are produced by spontaneous emission.
An excited atom drops to a lower level of its own accord and emits a photon in a random direction. A few of those photons happen to travel along the axis, and they set off the stimulated emission that builds the beam.
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