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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi bobbym,

Both the estimates are correct! Brilliant, bobbym!

II 60. What is the escape velocity from Earth in kilometers per hour or miles per hour?

II 61. In physical cosmology, the age of the universe is the time elapsed since the Big Bang. What is the current measurement of the age of the universe within the Lambda-CDM concordance model?

*The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parametrization of the Big Bang cosmological model in which the universe contains a cosmological constant, denoted by Lambda (Greek Λ), associated with dark energy, and cold dark matter (abbreviated CDM). It is frequently referred to as the standard model of Big Bang cosmology, because it is the simplest model that provides a reasonably good account of the following properties of the cosmos:*

* the existence and structure of the cosmic microwave background the large-scale structure in the distribution of galaxies the abundances of hydrogen (including deuterium), helium, and lithium the accelerating expansion of the universe observed in the light from distant galaxies and supernovae*

*The model assumes that general relativity is the correct theory of gravity on cosmological scales. It emerged in the late 1990s as a concordance cosmology, after a period of time when disparate observed properties of the universe appeared mutually inconsistent, and there was no consensus on the makeup of the energy density of the universe.*

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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**Relentless****Member**- Registered: 2015-12-15
- Posts: 631

Hello!

*Last edited by Relentless (2015-12-19 23:53:27)*

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi Relentless,

The answers, II 59, II 60, and II 61, are correct! Brilliant!

II 62. What is the volume of the Sun in cubic kilometers?

II 63. What is the Escape velocity (from the surface) of the Sun in kilometers per second?

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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**Relentless****Member**- Registered: 2015-12-15
- Posts: 631

62. I know that Earth is about 1 trillion cubic km. I know the Sun is something like 99.9% of the mass of the solar system. I know Jupiter is about 300 times larger than Earth. I guess that there is roughly 5 or 6 Jupiters' worth of mass in the rest of the Solar System (minus the Earth and Sun). Which puts the Earth at between one 1500th and one 1800th of one tenth of one percent of the Solar System, while the Sun is virtually all of it. I therefore estimate the volume of the Sun to be at least one and a half million and maybe 1.8 million times that of the Earth, or about 1.5 to 1.8 * 10^18 cubic km. How did I do? (:

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi Relentless,

Marvelous, Relentless, your Answer II 62 is very close!

II 64. The astronomical unit (symbol au, AU or ua) is a unit of length, roughly the distance from Earth to the Sun. However, that distance varies as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once a year. Originally conceived as the average of Earth's aphelion and perihelion, what is the distance in miles or kilometers? (The astronomical unit is used primarily as a convenient yardstick for measuring distances within the Solar System or around other stars. However, it is also a fundamental component in the definition of another unit of astronomical length, the parsec.)

II 65. What are Charon, Styx, Nix, Kerberos, and Hydra?

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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**Relentless****Member**- Registered: 2015-12-15
- Posts: 631

II 64.

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi Relentless,

Marvelous!

II 66. Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. Uranus is similar in composition to Neptune, and both have different bulk chemical composition from that of the larger gas giants Jupiter and Saturn. What is its mean radius in kilometers?

II 67. Neptune is the eighth and farthest planet from the Sun in the Solar System. It is the fourth-largest planet by diameter and the third-largest by mass. Among the giant planets in the Solar System, Neptune is the most dense. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 times the mass of Earth and slightly larger than Neptune. Neptune's outer atmosphere is one of the coldest places in the Solar System. At what temperature with its cloud tops approaching? (Temperatures at the planet's centre are approximately 5,400 K (5,100 °C)).

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi bobbym,

The Answer II 66 is correct! Excellent!

II 68. Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a giant planet with a mass one-thousandth that of the Sun, but two and a half times that of all the other planets in the Solar System combined. Jupiter is a gas giant, along with Saturn (Uranus and Neptune are ice giants). Jupiter was known to astronomers of ancient times. When viewed from Earth, Jupiter can reach an apparent magnitude of what? (bright enough for its reflected light to cast shadows, and making it on average the third-brightest object in the night sky after the Moon and Venus.)

II 69. What is the distance (Aphelion AU and Perihelion AU) from the planet Saturn?

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi bobbym,

The Answer II 69 is perfect! Brilliant!

II 70. Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. It is named after the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of -4.6, bright enough to cast shadows. What is the distance in Aphelion (AU or kilometers) and Perihelion (AU or kilometers)?

II 71. Mars is the fourth planet from the Sun and the second smallest planet in the Solar System, after Mercury. Named after the Roman god of war, it is often referred to as the "Red Planet" because the iron oxide prevalent on its surface gives it a reddish appearance. What is the distance in Aphelion (AU) and Perihelion (AU)?

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi bobbym,

Both the Answers, II 70 and II 71, are perfect! Remarkable!

II 72. What is the mean radius of Venus in kilometers?

II 73. What is the mean radius of Mars in kilometers?

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

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

II 74. Approximately, at what temperature degrees Fahrenheit and Kelvin be equal?

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

Neat work, bobbym!

II 75. How many known moons of Jupiter at present?

II 76. How many known moons of Saturn at present?

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

Both the Answers, II 75 and II 76, are close to the actual number. Good work, bobbym!

II 77. Libya is the fourth largest country in Africa, and is the 16th largest country in the world. State the area in square kilometers or square miles within the actual magnitude ± 10%.

II 78. Peru is a country in western South America. It is bordered in the north by Ecuador and Colombia, in the east by Brazil, in the southeast by Bolivia, in the south by Chile, and in the west by the Pacific Ocean. Peruvian territory was home to ancient cultures spanning from the Norte Chico civilization in Caral, one of the oldest in the world, to the Inca Empire, the largest state in Pre-Columbian America. State the land area of Peru of actual magnitude ± 10 %.

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

Good attempt (II 78), bobbym!

II 79. What is the population of Brazil? ((2013) World Bank)

II 80. What is the population of Saudi Arabia? ((2013) World Bank)

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

The Answer II 79 is close to the actual value. Good attempt, bobbym!

II 81. What is the approximate value of Planck constant in SI units?

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

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**bobbym****bumpkin**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606

Hi;

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**** Always satisfy the Prime Directive of getting the right answer above all else.**

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**Jai Ganesh****Administrator**- Registered: 2005-06-28
- Posts: 44,502

Hi;

Excellent, bobbym! The Answer II 81 is perfect.

II 82. Unicellular organisms are thought to be the oldest form of life, with early protocells possibly emerging around how many years?

II 83. In mathematics, the nth taxicab number, typically denoted Ta(n) or Taxicab(n), is defined as the smallest number that can be expressed as a sum of two positive cube numbers in n distinct ways. The most famous taxicab number is

.The concept was first mentioned by Bernard Frénicle de Bessy, and was made famous in the early 20th century by a story involving Srinivasa Ramanujan. In which year or century was it?

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

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