A new study conducted for the World Bank by Murdoch University's Institute for Science and Technology Policy (ISTP) has demonstrated that public transport is more efficient than cars. The study compared the proportion of money poured into transport by thirty-seven cities around the world. This included both the public and private costs of building, maintaining and using a transport system.The study found that the Western Australian city of Perth is a good example of a city with minimal public transport. As a result, 17% of its wealth went into transport costs. Some European and Asian cities, on the other hand, spent as little as 5%. As a consequence, these more efficient cities were able to put the money saved into attracting industry and jobs or creating a better place to live.Professor Newman, ISTP Director describes Melbourne as two cities: "A European city surrounded by a car-dependent one''. Melbourne's large tram network has greatly reduced car use in the inner city, but the outer suburbs have the same car-based structure as most other Australian cities. The increasing demand for accommodation in the inner suburbs of Melbourne suggests that people now prefer to live there.Newman believes there is a new, more general way of considering public transport issues. In the past, environmental and social justice were considered before economics. Newman, however, thinks the study demonstrates that "the auto-dependent city model is inefficient and very inadequate in both economic and environmental terms''.Supporters of the road networks often reject the models of cities with good public transport by saying that these systems would not work in their particular city. One objection is climate. Some people say their city could not make more use of public transport because it is either too hot or too cold. Newman rejects this, pointing out that public transport has been successful in both Toronto and Singapore and, in fact, checks have demonstrated no correlation between the use of cars and the climate. When it comes to other physical characteristics, road lobbies are in a stronger position. For example, Newman accepts it would be hard for a city with a lot of hills like Auckland to develop a really good rail network. However, he points out that both Hong Kong and Zurich have managed to make a success of their rail systems, even if they have more hills than most cities in the world. In fact, Newman believes the main reason for choosing one sort of transport instead of another is politics: "the more democratic the process, the more public transport is favored". He considers Portland, Oregon, a perfect example of this. Some years ago, the central government decided to finance the construction of a new road. However, local pressure groups called for a referendum and the money was spent on a railway instead, which worked extremely well. In the years that have followed, more and more rail systems have been put in, dramatically changing the nature of the city. In the UK, travel times to work had been stable for at least six centuries, and people generally avoided spending more than half an hour travelling to work. Trains and cars initially allowed people to live at greater distances without taking longer to reach their destination. However, public infrastructure did not grow with the increase in urban areas, and this caused enormous congestion problems and much longer commuting times. Many think that if people have more money they want to live further from the city centre where cars are the only practical means of transport. The example of European cities contradicts that. People are often wealthier than their American counterparts but do not use their cars as much. In Stockholm, car use has actually fallen in recent years as the city has become larger and wealthier. New studies show that developing cities in Asia, such as Jakarta and Bangkok, make more use of the car than wealthy Asian cities such as Tokyo and Singapore. In cities that developed later, the World bank and Asian Development Bank discouraged the building of public transport and people have been forced to depend on cars -- creating the massive traffic jams that characterize those cities. An alternative proposal is to convert cities that have been built for cars to rail use, by creating urban villages at hundreds of sites, mostly around railway stations.

In the study Melbourne emerges as

The use of private transport

The ISTP report showed that cities with well-developed public transport

Some people who prefer travelling by car do not agree with an increase in public transport becauseDeselect Answer

In the case of Portland, the most significant aspect governing the choice of trains was

When supernovae explode, they jettison matter into space at some 9,000 to 25,000 miles (15,000 to 40,000 kilometers) per second. These blasts produce much of the material in the universe -- including some elements, like iron, which make up our planet and even ourselves. Heavy elements are only produced in supernovae, so all of us carry the remnants of these distant explosions within our own bodies. Supernovae add enriching elements to space clouds of dust and gas, further interstellar diversity, and produce a shock wave that compresses clouds of gas to aid new star formation. But only a select few stars become supernovae. Many stars cool in later life to end their days as white dwarfs and, later, black dwarfs. But massive stars, many times larger than our own sun, may create a supernova when their core's fusion process runs out of fuel. Star fusion provides a constant outward pressure, which exists in balance with the star's own mass-driven, inward gravitational pull. When fusion slows, outbound pressure drops and the star's core begins to condense under gravity -- becoming ever denser and hotter. To outward appearances, such stars begin growing, swelling into bodies known as red super giants. But at their cores shrinking continues, making a supernova imminent. When a star's core contracts to a critical point a series of nuclear reactions is unleashed. This fusion staves off core collapse for a time -- but only until the core is composed largely of iron, which can no longer sustain star fusion. In a microsecond, the core may reach temperatures of billions of degrees Celsius. Iron atoms become crushed so closely together that the repulsive forces of their nuclei create a recoil of the squeezed core -- a bounce that causes the star to explode as a supernova and give birth to an enormous, superheated, shock wave.
Supernovae also occur in binary star systems. Smaller stars, up to eight times the mass of our own sun, typically evolve into white dwarfs. A star condensed to this size, about that of Earth, is very dense and thus has strong enough gravitational pull to gather material from the system's second star if it is close enough. If a white dwarf takes on enough mass it reaches a level called the Chandrasekhar limit. At this point the pressure at its center will become so great that runaway fusion occurs and the star detonates in a thermonuclear supernova. A supernova can light the sky up for weeks, and the massive transfer of matter and energy leaves behind a very different star. Typically only a tiny core of neutrons, a spinning neutron star, is left to evidence a supernova. Neutron stars give off radio waves in a steady stream or, as pulsars, in intermittent bursts. If a star was so massive (at least ten times the size of our sun) that it leaves behind a large core, a new phenomenon will occur. Because such a burned-out core has no energy source to fuse, and thus produces no outward pressure, it may become engulfed by its own gravity and turn into a cosmic sinkhole for energy and matter -- a black hole.

Supernovae from massive stars

Supernovae occur when

White dwarfs

During the process in which a star is transformed into a supernova

SupernovaeDeselect Answer

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In space consider a point  Q and a plane which is 1 away from Q. The intersection between this plane and the sphere with center Q and radius 2 is

By simplifying the expression 



where a and b are two non-zero real numbers different from each other, we obtainDeselect Answer

The least common multiple of monomials 8x³y⁶, 6x²y⁶z², x⁴y³ isDeselect Answer

The prime factorization of the number (2⁵-2³)⁴3² isDeselect Answer

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Which of these equations represents a straight line passing through the point (-2,3)  and perpendicular to the bisector of the first quadrant?

A solution of the equation  is log₃(2+x)²=6 isDeselect Answer

The product of 40 integer numbers is positive. From this information we can deduce that it is necessarily true that:

John doesn't believe that Anthony passed the professional certification exam, but he doesn't have any evidence to the contrary.
We can deduce that:Deselect Answer

As it is true that:
- all sparrows are birds
- all sparrows are small
- all birds are animals
- some animals don't eat leaves
it can be deduced that:Deselect Answer

Discussing their personal finances, four friends (Dilya, Gulzoda, Laziza e Tenkokuheya) state that:

- Dilya has less money than Laziza
- Gulzoda has less money than Laziza
- Laziza has more money than Tenkokuheya
- Gulzoda has more money than Dilya

Then, which of the following statements is NOT NECESSARILY correct?Deselect Answer

If it is true that:
- all engineers are logical thinkers
- Anthony is an engineer
- logical thinkers like scooters
which of the following statements is certainly NOT true?Deselect Answer

Discussing their personal finances, four friends (Alan, Brian, Conan e Donald) state that:
- Alan has less money than Conan
- Brian has less money than Conan
- Conan has more money than Donald
- Brian has more money than Alan

Then, which of the following statements is NOT NECESSARILY correct?Deselect Answer

Anna, Bruno, Carlo and Daniela are considering whether to go to Cortina next weekend.
We know that:
- if Carlo goes, Daniela will also go
- if Anna doesn't go, Daniela won't go either
- if Anna goes, Bruno will also go
Which of the following statements can be deduced?Deselect Answer

The product of 40 integer numbers is positive. From this information we can deduce that it is necessarily true that:Deselect Answer

Chef John noticed that, if he does not use a gas oven, roasted meat remains raw inside or becomes burnt outside (or both).
Therefore we can infer that:Deselect Answer

The great mathematician Countalot discovered the Incredible numbers; he does not know yet if they are finite or infinite, but he made the following conjecture:
If they are infinite, then at least one of them has 8 distinct prime factors.Deselect Answer

The product of 40 integer numbers is positive. From this information we can deduce that it is necessarily true that:Deselect Answer

Which of these diagrams illustrates the correct relationship between:
EVEN NUMBERS - MULTIPLES OF 12 - MULTIPLES OF 6?
Deselect Answer

How can you insert the + (plus) or the - (minus) sign in the following sequence of numbers :
14   16   13   12   11 
in order to have -6 as a result?
(Example: if I insert + -  in the sequence 5  6  7  the result is 5 + 6 - 7 = +4 , if I insert - + the result is 5 - 6 + 7 = +6)Deselect Answer

Which pair of numbers completes the following figure?
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Randall purchased a shirt for 19.44 dolars using a 20 dolars bill. If his correct change was returned in only dimes (0.10 dolars)  and  pennies (0.01 dolars), how many coins could Randall have received?Deselect Answer

If the dollar amount of sales at Store P was 800,000 dolar for 2006, what was the dollar amount of sales at that store for 2008?Deselect Answer

A washing machine takes 35 minutes to wash one load of laundry, and in between washing different loads of laundry it takes Derek 2 minutes to unload and another 4 minutes to reload the machine. If the washing machine begins washing one load of laundry at 12:30pm, how many loads of laundry can Derek wash and unload before 6:35pm?Deselect Answer

The figure above represents a rectangular garden with a walkway around it. The garden is 18 feet long and 12 feet wide. The walkway is uniformly 3 feet wide, and its edges meet at right angles. What is the area of the walkway?Deselect Answer

Approximately what percent of the faculty in humanities are non-adjunct faculty?Deselect Answer

Which pair of numbers x, y should be inserted into the following table?
Deselect Answer

Small molecules are used as the basic units in the synthesis of large food molecules.
Which statement is corred?Deselect Answer

When a is added to meat, amino acids are produced.
What is this substance?Deselect Answer

Which type of food is not digested fore being absorbed by the body?Deselect Answer

A girl holds her breath for 30 seconds, breathes out, and then breathes in. Compared with the air she breathes out, the air she breathes in contains less

Which statement is correct for most veins in the human body?Deselect Answer

in pea plants the ailele for tali, T, is dominant to the ailele for dwarf, t.
Which cross would produce plants in the proprtion of 1 tali : 1 dwarf?Deselect Answer

What are aileles?Deselect Answer

Which of the following processes involve mitosis?Deselect Answer

This diagram shows a section of DNA

How many hydrogen bonds would involved in holding these two strands togetherDeselect Answer

A length Of double-stranded DNA contains 180 nucleotides and for enzyme Z
What is the maximum of amino acids in enzyme X?Deselect Answer