# Math Is Fun Forum

Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫  π  -¹ ² ³ °

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## #7351 2022-06-30 00:29:35

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8457. Name the instrument that measures the absorbance of particular wavelengths of light by a specific solution. It is commonly used to determine the concentration of a known solute in a given solution by the application of the Beer–Lambert law, which states that the concentration of a solute is proportional to the absorbance.

#8458. Name the instrument that is a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. It consists of a cylinder composed of multiple metal contact segments on the rotating armature of the machine.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7352 2022-07-01 00:35:28

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8459. What is a Viscometer (also called Viscosimeter)?

#8460. What is a  Wattmeter?

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7353 2022-07-02 00:24:42

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8461 When was Antiseptic initiated?

#8462. Name the medication used to reduce pain, fever, or inflammation. Specific inflammatory conditions which aspirin is used to treat include Kawasaki disease, pericarditis, and rheumatic fever.

It is also used long-term to help prevent further heart attacks, ischaemic strokes, and blood clots in people at high risk. For pain or fever, effects typically begin within 30 minutes. It is a nonsteroidal anti-inflammatory drug (NSAID) and works similarly to other NSAIDs but also suppresses the normal functioning of platelets.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7354 2022-07-03 00:37:58

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8463. When was 'Adding Machine' invented?

#8464. When was the 'Arc lamp' invented approximately?

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7355 2022-07-04 00:02:32

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8465. When was the 'Atomic nucleus' discovered?

#8466. Name the the scientist (in the early 1800s) who noticed that chemical substances seemed to combine and break down into other substances by weight in proportions that suggested that each chemical element is ultimately made up of tiny indivisible particles of consistent weight.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7356 2022-07-05 00:35:09

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8467. The first patent for a ballpoint pen was issued on 30 October 1888 who was attempting to make a writing instrument that would be able to write "on rough surfaces—such as wood, coarse wrapping-paper, and other articles" which fountain pens could not. Name the inventor.

#8468. Name the inventor who received a patent for the modern invention of Barbed wire in 1874 after he made his own modifications to previous versions.  ( (January 18, 1813 – October 9, 1906) He was an American businessman and farmer. He was the inventor of the modern barbed wire. In 1898, he donated land for the Northern Illinois State Normal School in DeKalb, Illinois, which was renamed as Northern Illinois University in 1957.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7357 2022-07-06 00:07:17

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8469. Name the sportsman : (born 21 August 1986) He is a retired Jamaican sprinter, widely considered to be the greatest sprinter of all time. He is the world record holder in the 100 metres, 200 metres, and 4 × 100 metres relay.

An eight-time Olympic gold medallist, he is the only sprinter to win Olympic 100 m and 200 m titles at three consecutive Olympics (2008, 2012, and 2016). He also won two 4 × 100 relay gold medals. He gained worldwide fame for his double sprint victory in world record times at the 2008 Beijing Olympics, which made him the first person to hold both records since fully automatic time became mandatory.

#8470. Name the athlete : (born 15 July 1992) He is a South African track and field sprinter who competes in the 200 and 400 metres. In the 400 metres, he is the current world and Olympic record holder which he broke in the Olympic finals. He also holds the world-best time in the 300 metres.

In the 2016 Olympic Games men's 400m, he won the gold medal with a world record time of 43.03 seconds (reaction time 0.181 s) at age 24 years and 30 days, beating the time of 43.18 seconds set by Michael Johnson during the 1999 World Championships in Athletics in Seville, Spain.

In 2016, he became the first sprinter in history to have run the 100 metres in under 10 seconds, 200 metres in under 20 seconds, and 400 metres in under 44 seconds.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7358 2022-07-07 03:53:09

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8471. Name the inventor of the first practical pneumatic tire was made in 1887 for his son's bicycle, in an effort to prevent the headaches his son had while riding on rough roads.

#8472. Name the inventor generally credited with the invention of bifocals. He decided to saw his lenses in half so he could see the expressions of speakers of French at court, the only way he could understand them.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7359 2022-07-08 00:10:04

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8473. The Wright brothers invented and flew the first airplane, recognized as "the first sustained and controlled heavier-than-air powered flight". In which year was it? (Orville Wright (August 19, 1871 – January 30, 1948) and Wilbur Wright (April 16, 1867 – May 30, 1912), together known as the Wright brothers, were American aviation pioneers generally credited with inventing, building, and flying the world's first successful motor-operated airplane.)

#8474. Henri Giffard became the first person to make an engine-powered flight when he flew 27 km (17 mi) in a steam-powered airship. In which year was it? (Airships would develop considerably over the next two decades.)

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7360 2022-07-09 00:06:57

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8475. Electromagnets are widely used as components of other electrical devices, such as motors, generators, electromechanical solenoids, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment. Electromagnets are also employed in industry for picking up and moving heavy iron objects such as scrap iron and steel.

When was the electromagnet invented?

#8476. Electromagnetic or magnetic induction is the production of an electromotive force across an electrical conductor in a changing magnetic field.

When was the Electromagnetic induction discovered?

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7361 2022-07-10 00:03:36

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8477. Name the American industrialist, founder of the Otis Elevator Company, and inventor of a safety device that prevents elevators from falling if the hoisting cable fails. (August 3, 1811 – April 8, 1861).

#8478. Name the American inventor and early pioneer in radio and in the development of sound-on-film recording used for motion pictures. (August 26, 1873 – June 30, 1961) He had over 300 patents worldwide, but also a tumultuous career—he boasted that he made, then lost, four fortunes. He was also involved in several major patent lawsuits, spent a substantial part of his income on legal bills, and was even tried (and acquitted) for mail fraud. His most famous invention, in 1906, was the three-element "Audion" (triode) vacuum tube, the first practical amplification device.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7362 2022-07-11 00:03:39

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8479. Name the French chemist and pharmacist who won the 1906 Nobel Prize in Chemistry for his work in isolating fluorine from its compounds. ((28 September 1852 – 20 February 1907) He was one of the original members of the International Atomic Weights Committee.

#8480. Name the Romanian inventor who received a French patent on May 25, 1827, for the invention of a fountain pen with a barrel made from a large swan quill.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7363 2022-07-12 00:05:30

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8481. Name the American inventor, entrepreneur, and naturalist, considered the founder of the modern frozen food industry. (December 9, 1886 – October 7, 1956).

#8482. Name the Scottish engineer and inventor (21 August 1754 – 15 November 1839). He was the inventor of the oscillating cylinder steam engine, and gas lighting is attributed to him in the early 1790s, as well as the term "gasometer".

He also made innovations to the steam engine, including the sun and planet gear and D slide valve. He invented the steam gun and the pneumatic tube message system, and worked on one of the first British paddle steamers to cross the English Channel. He built a prototype steam locomotive in 1784, and made a number of discoveries in chemistry.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7364 2022-07-13 00:07:07

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8483. Zénobe Théophile Gramme (4 April 1826 – 20 January 1901) was a Belgian electrical engineer. What did he invent?

#8484. Name the American inventor (1840–1917) who developed a knotting device to bind grain bundles with twine. It became the foundation for all farm grain binding machinery and was used extensively by all the major manufacturers of large grain harvesting machines in the late 19th and early 20th centuries. Hi knotting device was a major landmark in the mechanization of agriculture and aided the development of the western wheat fields of the United States.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7365 2022-07-14 00:06:28

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,,

#8485. A phonograph, in its later forms also called a gramophone (as a trademark since 1887, as a generic name in the UK since 1910) or since the 1940s called a record player, or more recently a turntable, is a device for the mechanical and analogue recording and reproduction of sound. The sound vibration waveforms are recorded as corresponding physical deviations of a spiral groove engraved, etched, incised, or impressed into the surface of a rotating cylinder or disc, called a "record".

When was the phonograph invented by Thomas Edison?

#8486. Name the American inventor and entrepreneur (October 12, 1860 – June 16, 1930), most famous for construction, two years after Hermann Anschütz-Kaempfe, of the gyrocompass and as founder of the Gyroscope Company in his name. He was known as the "father of modern navigation technology".

His compasses and stabilizers were adopted by the United States Navy and used in both world wars. He also worked closely with Japanese companies and the Japanese government and was honored after his death with a volume of reminiscences published in Japan.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7366 2022-07-15 00:13:36

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8487. Name the Russian–American aviation pioneer in both helicopters and fixed-wing aircraft (May 25, 1889 – October 26, 1972). His first success came with the S-2, the second aircraft of his design and construction. His fifth airplane, the S-5, won him national recognition as well as F.A.I. license number 64. His S-6-A received the highest award at the 1912 Moscow Aviation Exhibition, and in the fall of that year the aircraft won first prize for its young designer, builder and pilot in the military competition at Saint Petersburg.

#8488. Name the French astronomer (22 February 1824 – 23 December 1907) who, along with English scientist Joseph Norman Lockyer, is credited with discovering the gaseous nature of the solar chromosphere, and with some justification the element helium.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7367 2022-07-16 00:17:06

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8489. What was Sir John Isaac Thornycroft FRS (1 February 1843 – 28 June 1928) known for?

#8490. Sir Timothy John Berners-Lee (born 8 June 1955), also known as TimBL, is an English computer scientist best known as the inventor of the World Wide Web. He is a Professorial Fellow of Computer Science at the University of Oxford and a professor at the Massachusetts Institute of Technology (MIT). Berners-Lee proposed an information management system, then implemented the first successful communication between a Hypertext Transfer Protocol (HTTP) client and server via the Internet in mid-November.

When was it?

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7368 2022-07-17 00:09:38

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8491. When is the 'International Albinism Awareness Day' celebrated? (International Albinism Awareness Day (IAAD) is celebrated annually to celebrate the human rights of persons with albinism worldwide.

Albinism is a congenital condition characterized in humans by the partial or complete absence of pigment in the skin, hair and eyes. Albinism is associated with a number of vision defects, such as photophobia, nystagmus, and amblyopia. Lack of skin pigmentation makes for more susceptibility to sunburn and skin cancers.

#8492. When is the 'International Tea Day' observed? (The concerning resolution was adopted on December 21, 2019 and calls on the United Nations Food and Agriculture Organization (FAO) to lead the observance of the Day.

The International Tea Day aims to raise awareness of the long history and the deep cultural and economic significance of tea around the world. The goal of the day is to promote and foster collective actions to implement activities in favour of the sustainable production and consumption of tea and raise awareness of its importance in fighting hunger and poverty.)

An International Tea Day has been celebrated on December 15, since 2005, in tea producing countries like India, Sri Lanka, Nepal, Vietnam, Indonesia, Bangladesh, Kenya, Malawi, Malaysia, Uganda and Tanzania. International Tea Day aims to draw global attention of governments and citizens to the impact of the global tea trade on workers and growers, and has been linked to requests for price supports and fair trade.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7369 2022-07-17 00:10:33

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8491. When is the 'International Albinism Awareness Day' celebrated? (International Albinism Awareness Day (IAAD) is celebrated annually to celebrate the human rights of persons with albinism worldwide.

Albinism is a congenital condition characterized in humans by the partial or complete absence of pigment in the skin, hair and eyes. Albinism is associated with a number of vision defects, such as photophobia, nystagmus, and amblyopia. Lack of skin pigmentation makes for more susceptibility to sunburn and skin cancers.

#8492. When is the 'International Tea Day' observed? (The concerning resolution was adopted on December 21, 2019 and calls on the United Nations Food and Agriculture Organization (FAO) to lead the observance of the Day.

The International Tea Day aims to raise awareness of the long history and the deep cultural and economic significance of tea around the world. The goal of the day is to promote and foster collective actions to implement activities in favour of the sustainable production and consumption of tea and raise awareness of its importance in fighting hunger and poverty.)

An International Tea Day has been celebrated on December 15, since 2005, in tea producing countries like India, Sri Lanka, Nepal, Vietnam, Indonesia, Bangladesh, Kenya, Malawi, Malaysia, Uganda and Tanzania. International Tea Day aims to draw global attention of governments and citizens to the impact of the global tea trade on workers and growers, and has been linked to requests for price supports and fair trade.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7370 2022-07-18 00:11:00

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8493. When is the 'UNESCO World Engineering Day for Sustainable Development' celebrated? (The World Engineering Day for Sustainable Development (acronym: WED) is one of International Days UNESCO and is celebrated every year. It was proclaimed by UNESCO General Conference on 25 November 2019, based on a proposal by the World Federation of Engineering Organizations (WFEO)).

#8494. When is 'International Day for the Preservation of the Ozone Layer' (informally and simply called Ozone Day) is celebrated designed by the United Nations General Assembly? (This designation had been made on December 19, 2000, in commemoration of the date, in 1987, on which nations signed the Montreal Protocol on Substances that Deplete the Ozone Layer. In 1994, the UN General Assembly proclaimed 16 September the International Day for the Preservation of the Ozone Layer, commemorating the date of the signing, in 1987, of the Montreal Protocol on Substances that Deplete the Ozone Layer.)

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7371 2022-07-19 00:06:47

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8495. Name the English engineer, inventor (1 June 1907 – 8 August 1996) and Royal Air Force (RAF) air officer. He is credited with inventing the turbojet engine. A patent was submitted by Maxime Guillaume in 1921 for a similar invention; however, this was technically unfeasible at the time. His jet engines were developed some years earlier than those of Germany's Hans von Ohain, who designed the first-to-fly (but never operational) turbojet engine.

#8496. Name the American physicist  (July 28, 1915 – January 27, 2015). He worked on the theory and application of the maser, for which he obtained the fundamental patent, and other work in quantum electronics associated with both maser and laser devices. He shared the 1964 Nobel Prize in Physics with Nikolay Basov and Alexander Prokhorov.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7372 2022-07-20 00:06:25

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8497.  Name the American inventor, electrical engineer and entrepreneur (May 3, 1922 – April 15, 2019) who was awarded 76 US patents as an individual or as part of a team, as well as many corresponding patents. His patents have had an impact relating to home washing machines and the preparation of food in both the Quick Service Restaurant (QSR) industry and fine dining. Technologies He developed while an engineer at General Electric are still in use after more than fifty years. His patent for the modern "Washing Machine" (US 3257830 A), licensed in 1965 to General Electric has been referenced in over 40 subsequent patents.

He also invented new ways to cook and hold food, including the Collectramatic, the first pressurized fryer that did not require interrupting production to frequently filter shortening while cooking. He also invented Controlled Vapor Technology, a patented cooking method that uses water vapor to prepare and safely hold food.

#8498. In what later became the United States, the pointed lightning rod conductor, also called a lightning attractor or Franklin rod, was invented by Benjamin Franklin as part of his groundbreaking exploration of electricity. Although not the first to suggest a correlation between electricity and lightning, Franklin was the first to propose a workable system for testing his hypothesis. Franklin speculated that, with an iron rod sharpened to a point, "The electrical fire would, I think, be drawn out of a cloud silently, before it could come near enough to strike." Franklin speculated about lightning rods for several years before his reported kite experiment.

In which year was it?

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7373 2022-07-21 00:08:19

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8499. In which year was Linoleum in Chiswick patented by Frederick Walton?

#8500. Name the British inventor and mining engineer (13 April 1771 – 22 April 1833). The son of a mining captain, and born in the mining heartland of Cornwall, he was immersed in mining and engineering from an early age. He was an early pioneer of steam-powered road and rail transport, and his most significant contributions were the development of the first high-pressure steam engine and the first working railway steam locomotive. The world's first locomotive-hauled railway journey took place on 21 February 1804, when his unnamed steam locomotive hauled a train along the tramway of the Penydarren Ironworks, in Merthyr Tydfil, Wales.

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7374 2022-07-22 00:03:53

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8501. When is the 'International Literacy Day' observed day? (International Literacy Day is an international observance, celebrated each year, that was declared by UNESCO on 26 October 1966 at the 14th session of UNESCO's General Conference. It was celebrated for the first time in 1967. Its aim is to highlight the importance of literacy to individuals, communities and societies. Celebrations take place in several countries.)

#8502. When is the 'International Day for Tolerance' observed? (The International Day for Tolerance is an annual observance day declared by UNESCO in 1995 to generate public awareness of the dangers of intolerance.

The International Day for Tolerance is now celebrated every year, in recognition of the Paris Declaration which was signed that day in 1995 by 185 member states.)

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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## #7375 2022-07-23 00:09:52

ganesh
Registered: 2005-06-28
Posts: 37,965

### Re: General Quiz

Hi,

#8503. When is the 'International Day of Women and Girls in Science' observed? (The International Day of Women and Girls in Science is an annual observance adopted by the United Nations General Assembly to promote the full and equal access and participation of females in Science, Technology, Engineering and Mathematics (STEM) fields.)

#8504. When is the 'International Day of Charity' observed? (It was declared by the United Nations General Assembly in 2012. The prime purpose of the International Day of Charity is to raise awareness and provide a common platform for charity related activities all over the world for individuals, charitable, philanthropic and volunteer organizations for their own purposes on the local, national, regional and international level.)

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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