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August 27, 2014

Homework Help: Science: Earth

Recent Homework Questions About Earth

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Physics
A deep space probe moves away from the earth with a speed of 0.75c. An antenna on the probe requires 3.00s probe time to rotate through 1 revolution. How much time is required for 1.00 rev according to an observer on Earth?
Wednesday, May 2, 2012 at 8:25pm

Physics
Two stars are 8 light years from earth (a light year is the distance light travels in one year). The 550 nm light from the two stars can be barely distinguished in the diffraction pattern of 90 cm wide single slit. How far apart are the stars?
Wednesday, May 2, 2012 at 8:24pm

physics
the magnitude of earths magnetic field at the magnetic north pole is 61/1000000.(a) determine the magnitude of the dipole moment of the earth (b)suppose an additional field due to the current in wire around the equator is used to make the net field at the pole zero,what is the...
Tuesday, May 1, 2012 at 12:59pm

earth
About how fast will it be traveling on average? Assume that its trajectory is close to a straight line. Give your answer in {\rm AU/yr} and in {\rm km/hr}.
Tuesday, May 1, 2012 at 3:03am

Physics
At a certain distance from the center of the Earth, a 4.00-kg object has a weight of 1.95 N. Calculate this distance.
Monday, April 30, 2012 at 9:50am

Enviro Science
2. The water resources of Earth are located in a. salt water found in the ocean b. freshwater found in icecaps and glaciers c. fresh water found in rivers, lakes, and streams d. all of the above C 4. Weather is the state of the atmosphere at a moment in time and at any ...
Sunday, April 29, 2012 at 8:45pm

Physics
If a projectile is launched from Earth with a speed equal to the escape speed, how high above the Earth's surface is it when its speed is three-fifths the escape speed? I keep getting the answer 2.56x10^6 m after solving it a few different ways. Help would be great.
Saturday, April 28, 2012 at 6:24pm

trig-math
4. A carpenter wants to be sure that the corner of a building is square and measures 6.0 ft and 8.0 ft along the sides. How long should the diagonal be? A. 12 ft B. 10 ft C. 11 ft D. 14 ft 5. A wheel 5.00 ft in diameter rolls up a 15.0° incline. How far above the base of ...
Saturday, April 28, 2012 at 4:32pm

math-TRIG
1. Which angle measure is consistent with all of the following criteria? (i) The reference angle is 40°. (ii) The angle is more than one revolution. (iii) The angle's terminal side is in Quadrant II. (iv) The angle isn't positive. A. –580° B. –500°...
Saturday, April 28, 2012 at 1:46pm

physics
If a projectile is launched vertically from the Earth with a speed equal to the escape speed, how far from the Earth's center is it when its speed is 1/9 of the escape speed?
Saturday, April 28, 2012 at 12:35am

physics
On July 15, 2004, NASA launched the Aura spacecraft to study the earth's climate and atmosphere. This satellite was injected into an orbit 705 {\rm km} above the earth's surface, and we shall assume a circular orbit. How many hours does it take this satellite to make ...
Friday, April 27, 2012 at 5:47pm

Earth Science
According to the condensation theory, the most important factor for the formation of our planets was _____.
Thursday, April 26, 2012 at 4:41pm

Earth Science
Which of the following is true: -Relative dating tells us how long ago something existed -Disconformities are less common but usually far more conspicuous because the strata on either side are essentially -Estimates indicate that the North American continent is being lowered ...
Wednesday, April 25, 2012 at 5:32pm

Enviro Science
4. The Earth's tectonic plates and earthquakes are related because a. most earthquakes take place at or near tectonic boundaries b. during an eruption, the plates slip past one another c. of the measure of energy released by the earthquake, called magnitude d. an ...
Tuesday, April 24, 2012 at 2:04pm

Enviro Science
Describe the diversity of species on Earth, relating the difference between known numbers and estimated numbers Thanks -MC
Tuesday, April 24, 2012 at 12:49am

biology
What geological process is used to explain how nearly identical animals that cannot swim, are found on continents separated by large oceans? What is the half-life of Uranium 238 and what did we use that radioisotope to date as the oldest item on Earth?
Saturday, April 21, 2012 at 1:29pm

earth
1.What's the heat trapping action of gases in the atmosphere?
Thursday, April 19, 2012 at 9:16pm

English
ms. sue you please help me with story questions? if you have time then this be story Field of Broken Dreams by Sharon Butala My memories of drives in the country when I was a child in the 1940s and early 1950s, after the devastation of the 1930s, are of abandoned farmstead ...
Thursday, April 19, 2012 at 8:54pm

Math
The tail of a giant kangaroo is attached by a giant rubber band to a stake in the ground. A flea is sitting on top of the stake eyeing the kangaroo (hungrily). The kangaroo sees the flea leaps into the air and lands one mile from the stake (with its tail still attached to the ...
Thursday, April 19, 2012 at 4:57pm

Science
Which of the following is a star? Earth Sun Moon a Comet? Sun?
Thursday, April 19, 2012 at 4:42pm

physics
Electronic types neglect the force of gravity on electrons.To see why, compute the force of Earth's gravity on an electron and compare it with the force exerted on the electron by an electric field of magnitude 6000 V/m (a relatively small field). The mass of an electron ...
Wednesday, April 18, 2012 at 7:17pm

earth
need help
Tuesday, April 17, 2012 at 9:14pm

physics
What is the angular speed in rev/min of the Earth as it orbits around the sun? I'm confused with this problem. I know we have to convert from rad/s to rev/rad to s/min in order to get the units as rev/min. But I don't know what to use for rad/s
Tuesday, April 17, 2012 at 6:00pm

physics
Assume the Earth is a sphere with its mass evenly distributed throughout. Find the moment of inertia of the Earth about its axis of rotation.
Tuesday, April 17, 2012 at 4:18pm

physics
Two pellets, each with a charge of 0.80 microcoulomb (8.0×10−7 C), are located 4.0 cm (4.0×10−2 m) apart. Find the electric force between them, which I solved for 3.6 N. I am stuck on the next part: What would be the mass of an object that would ...
Tuesday, April 17, 2012 at 4:59am

physics
the energy received by the earth from the sun is 1400w/m2. Assuming that the sun is a black body radiator and the ratio of the radius of the earth's orbit to the sun's radius is 216. Calculate the surface temperature of the sun. Stefan constant = 0.000000057w/m2 k4.
Monday, April 16, 2012 at 4:49pm

physics
Two stars are 3.80 1011 m apart and are equally distant from the earth. A telescope has an objective lens with a diameter of 1.19 m and just detects these stars as separate objects. Assume that light of wavelength 550 nm is being observed. Also assume that diffraction effects...
Sunday, April 15, 2012 at 7:29pm

Science
Why are space telescopes able to make better observations in the ultraviolet and infrared ranges than ground-based telescopes? A)space telescopes are closer to the objects that they are observing B) the atmosphere absorbs or reflects much of the UV and IR radiation C) space ...
Sunday, April 15, 2012 at 7:17pm

Earth/Space Science
Earth's axis tilts at an angle of 23.5 degrees relative to its orbit. Analyze the climate conditions that would exist at the poles and the equator if the axis were parallel to the orbit.
Sunday, April 15, 2012 at 6:43pm

physics please help !
A helicopter is ascending vertically with a speed of 5.20m/s . At a height of 110m above the Earth, a package is dropped from a window. How much time does it take for the package to reach the ground? [Hint: for the package equals the speed of the helicopter.]
Sunday, April 15, 2012 at 6:40pm

physics
a helicopter is ascending vertically with a speed of 5.20 m/s. at a height of 110 m above the Earth, a package is dropped from a window. how much time does it take for the package to reach the ground ? (hint: v0 for the package equals the speed of the helicopter).
Sunday, April 15, 2012 at 2:55pm

physics
a helicopter is ascending vertically with a speed of 5.20 m/s. at a height of 100 m above the Earth, a package is dropped from a window. how much time does it take for the package to reach the ground ? (hint: v0 for the package equals the speed of the helicopter). thank you !
Sunday, April 15, 2012 at 2:54pm

intro. to physics
a helicopter is ascending vertically with a speed of 5.20 m/s. at a height of 100 m above the Earth, a package is dropped from a window. how much time does it take for the package to reach the ground ? (hint: v0 for the package equals the speed of the helicopter). thank you !
Sunday, April 15, 2012 at 12:15pm

physics
Electronic types neglect the force of gravity on electrons.To see why, compute the force of Earth's gravity on an electron and compare it with the force exerted on the electron by an electric field of magnitude 6000 V/m (a relatively small field). The mass of an electron 9...
Saturday, April 14, 2012 at 10:30pm

earth
If a satalite weighs 90 kg at 10000 miles from the earth, how far away is it when it weighs 10 kg?
Thursday, April 12, 2012 at 10:44pm

Physics
A satellite used in a cellular telephone network has a mass of 2160 kg and is in a circular orbit at a height of 670 km above the surface of the earth. What is the gravitational force Fgrav on the satellite? Take the gravitational constant to be = 6.67×10−11 N*m^2/...
Thursday, April 12, 2012 at 4:44pm

Physics
At what distance above the surface of the earth is the acceleration due to the earth's gravity 0.790 m/s^2 if the acceleration due to gravity at the surface has magnitude .
Thursday, April 12, 2012 at 4:42pm

Physics
Given that acceleration due to gravity at the surface of the earth is 9.8N/kg, estimate a value for the mass of the earth. G=6.7x10^-11
Wednesday, April 11, 2012 at 6:40pm

physics
A space shuttle orbiting Earth at an altitude of 295 km completes an orbit in 90.0 min. Calculate its acceleration and compare it to the acceleration at Earth’s surface.
Wednesday, April 11, 2012 at 6:31pm

physcis ! HELP !!!!
which of collowing situations describe a particle that might have a non-zero velocity? canbe more than one A) a particle that has a constant position as a function of time B) a particle that has its position changing as a fnction of time c)when you graph the particle's ...
Tuesday, April 10, 2012 at 6:00pm

physics
which of collowing situations describe a particle that might have a non-zero velocity? canbe more than one A) a particle that has a constant position as a function of time B) a particle that has its position changing as a fnction of time c)when you graph the particle's ...
Tuesday, April 10, 2012 at 5:33pm

English
I have been writing this story for English class and would love some input on what i should add to this story. I don't want it to make it a sappy story either. Also sorry for the grammar errors i haven't perfected it yet. The last man on earth sat alone in his room, ...
Tuesday, April 10, 2012 at 3:21pm

Just Curious
A few questions out of curiosity. What does jiskha mean? And what is your view point of Pluto Since Pluto is no longer considered a planet, do you think it should still e called a planet? Not just dwarf planet, but a planet like Mars or Earth? Thanks and sorry for any bother...
Tuesday, April 10, 2012 at 2:49pm

physics
The sun is 1.5 1011 m from the earth. (a) Over what surface area is solar radiation spread at this distance? (b) What is the total power radiated by the sun? (The sun delivers energy to the surface of the earth at a rate of approximately 1400 W/m2.) (c) Treating the sun as a ...
Monday, April 9, 2012 at 1:05pm

English
Good Easter to you and your family, too, Writeacher. I urgently need you to check this rephrase of the modern translation of the fight between Beowulf and Grendel by Seamus Heaney. I need to be more precise in the description of the fight. Nor did the creature keep him waiting...
Sunday, April 8, 2012 at 5:49pm

physics
State how the centripetal force is provided in the case of a satelite orbiting the earth
Sunday, April 8, 2012 at 5:57am

Math
A comet passed by earth in the year 1835 It passes by every 60 years Based on this information in which of the following years can be the comet be expected to Pass by earth A : 2035 B: 2060 C: 2075 D: 2080
Saturday, April 7, 2012 at 10:45pm

Science
green house effect influences the temperature on Earth because try not to give a link
Saturday, April 7, 2012 at 12:51pm

Science
I need a hypothesis on: How does the green house effect influence temperature on Earth? Can you plz not give a link that doesn't help much
Friday, April 6, 2012 at 6:39pm

physics
Determine the magnitude of the force of gravity acting on a 340 kg satellite , 850 km above Earth's surface.
Friday, April 6, 2012 at 6:21pm

Physics Question
Twins who are 19.0 years of age leave the earth and travel to a distant planet 12.0 light-years away. Assume that the planet and earth are at rest with respect to each other. The twins depart at the same time on different spaceships. One twin travels at a speed of 0.854c, and ...
Friday, April 6, 2012 at 4:32pm

Physics help please
Twins who are 19.0 years of age leave the earth and travel to a distant planet 12.0 light-years away. Assume that the planet and earth are at rest with respect to each other. The twins depart at the same time on different spaceships. One twin travels at a speed of 0.854c, and ...
Friday, April 6, 2012 at 1:18pm

earth science
what radioactive isotope would be most useful in dating a mastodont bone ?why?
Friday, April 6, 2012 at 12:11pm

Science
If the distance from the moon to the Earth decrease from 230,000 miles (which it is today) to 20,000 miles, what affect would this have on the tides?
Friday, April 6, 2012 at 3:40am

physics
Determine the magnitude of the force of gravity acting on a 340 kg satellite, 850 km above Earth's surface
Thursday, April 5, 2012 at 9:47pm

Current/Magnetic force
A high voltage power line carries a current of 110 A at a location where the Earth's magnetic fields has a magnitude of 5.9 x 10^-4 T and points north at an angle of72 degrees below the horizontal (toward the earth surface). Find the direction and magnitude of the magnetic...
Thursday, April 5, 2012 at 1:55pm

physics
At a certain location, the solar power per unit area reaching Earth's surface is 200 W/m^2, averaged over a 24-hour day.If the average power requirement in your home is 2.8 kW and you can convert solar power to electric power with 8.0 % efficiency, how large a collector ...
Wednesday, April 4, 2012 at 5:51pm

Earth/Space Science
Cloud seeding, which causes rain by introducing condensation into a cloud, has been used to bring precipitation to areas experiencing drought. Analyze the benefits and risks of cloud seeding.
Wednesday, April 4, 2012 at 5:42pm

physics
At a certain location, the solar power per unit area reaching Earth's surface is 200 W/m^2, averaged over a 24-hour day.If the average power requirement in your home is 2.8 kW and you can convert solar power to electric power with 8.0 % efficiency, how large a collector ...
Tuesday, April 3, 2012 at 3:40pm

physics
Steel expands 11 parts in a million for each 1 degree C change. Consider a 40,000 km steel pipe that forms a ring to fit snugly all around the circumference of the Earth. Suppose people along its length breathe on it so as to raise its temperature 0.80 degree C. The pipe gets...
Tuesday, April 3, 2012 at 8:08am

science
Which statement correctly describes the Sun and earth?
Monday, April 2, 2012 at 9:53pm

PHYSICS
A 5450-m^3 blimp circles Fenway Park duing the World Series, suspended in the earth's 1.21-kg/m^3 atmosphere. The density of the helium in the blimp is 0.178 kg/m^3. A) What is the buoyant force that suspends the blimp in the air? B) How does this buotant force compare to ...
Monday, April 2, 2012 at 9:42pm

Earth/Space Science
How does damage to the ozone layer cause a threat to humans? A. It increases radiation of heat from Earth into space. B. It allows damaging infrared radiation to penetrate the atmosphere. C. It allows damaging ultraviolet radiation to penetrate the atmosphere. D. It increases ...
Monday, April 2, 2012 at 6:25pm

physics
The force of gravity at Earth's surface on an astronaut is 634N. What is the force of gravity on the same person at each of the following distances, in multiples of Earth's radius, from the centre of Earth? A)2 B)5 C)10 D)17.2
Monday, April 2, 2012 at 5:33pm

physics
The mass of Earth can be calculated using the fact that the weight of an object (in newtons) is equal to the force of gravity between the object and Earth. Given that the radius of Earth is 6.4*10^6m , determine its mass
Monday, April 2, 2012 at 5:27pm

physics
A spacecraft circling the moon at a distance of 384,000 km from the earth communicates by radio with a person on earth. How much time elapses between the sending and receiving of a signal?
Monday, April 2, 2012 at 10:33am

physics
Radioactive decay of granite and other rocks in Earth's interior provides sufficient energy to keep the interior molten, to heat lava, and to provide warmth to natural hot springs. This is due to the average release of about 0.03 J per kilogram each year.Find an increase ...
Sunday, April 1, 2012 at 10:57pm

physics
Steel expands 11 parts in a million for each 1 degree C change. Consider a 40,000 km steel pipe that forms a ring to fit snugly all around the circumference of the Earth. Suppose people along its length breathe on it so as to raise its temperature 0.80 degree C. The pipe gets ...
Sunday, April 1, 2012 at 10:46pm

physics
A uniform horizontal wire with a linear mass density of 0.48 g/m carries a 1.9 A current. It is placed in a constant magnetic field, with a strength of 3.5 10-3 T, that is horizontal and perpendicular to the wire. Neglect the magnetic field of the Earth. (a) As the wire moves ...
Sunday, April 1, 2012 at 4:30pm

science
why an astronaut would be able to lift heavy equipment more easily on the moon thanon earth?
Sunday, April 1, 2012 at 2:50pm

physics
Calculate Earth's force of gravity on each of two steel balls of masses 6.0kg and 12.0kg I the forces of gravity on the 12-kg ball is greater than that on the other ball, why do the two balls accelerate at the same rate when dropped?
Sunday, April 1, 2012 at 1:29am

physics
A spacecraft circling the moon at a distance of 384,000 km from the earth communicates by radio with a person on earth. How much time elapses between the sending and receiving of a signal?
Saturday, March 31, 2012 at 10:44am

physics
Steel expands 11 parts in a million for each 1 degree C change. Consider a 40,000 km steel pipe that forms a ring to fit snugly all around the circumference of the Earth. Suppose people along its length breathe on it so as to raise its temperature 0.80 degree C. The pipe gets ...
Saturday, March 31, 2012 at 10:15am

physics
The weight of the atmosphere above 1 m^2 of Earth's surface is about 100,000 N. Density, of course, becomes less with altitude. But suppose the density of air were a constant 1.2 kg/m/s^3. Calculate where the top of the atmosphere would be.
Saturday, March 31, 2012 at 9:28am

6th Grade History
Questions: 1) a priest who brought Christianity to Ireland 2) a separation of the two most important branches of Christianity 3) from this country monks traveled the continent of Europe establishing monasteries. name the country? 4)an iconoclast, or image breaker, is known ...
Friday, March 30, 2012 at 7:23pm

Physics
The earth has a radius of 6.38 106 m and turns on its axis once every 23.9 h. A. What is the tangential speed (in m/s) of a person living in Ecuador, a country that lies on the equator? (b) At what latitude (i.e., the angle θ in the drawing) is the tangential speed two-...
Friday, March 30, 2012 at 6:07pm

physics
Use these magnitudes of the forces of gravity at Earth's surface to determine the masses of the objects on which they act A)0.98N. B)62N C)44.5MN
Friday, March 30, 2012 at 5:57pm

physics
Use these magnitudes of the forces of gravity at Earth's surface to determine the masses of the objects on which they act A)0.98N. B)62N C)44.5MN
Friday, March 30, 2012 at 5:38pm

Astronomy
Suppose you weigh 105 . How much would you weigh on other planets in our solar system? Assume you can stand either on the surface or in an airplane in the planet's atmosphere. (Hint: Recall from Chapter Light and Matter that weight is mass times the acceleration of gravity...
Friday, March 30, 2012 at 2:37am

Math
The distance to the nearest 100000 km from Earth to the moon is given as 400000 km.The average speed to the nearest 500 km/h of a rocket to the moon is given as 3500 km/h.Calculate the greatest and least time it could take the rocket to reach the moon.
Friday, March 30, 2012 at 1:00am

physics
The weight of the atmosphere above 1 m^2 of Earth's surface is about 100,000 N. Density, of course, becomes less with altitude. But suppose the density of air were a constant 1.2 kg/m/s^3. Calculate where the top of the atmosphere would be.
Thursday, March 29, 2012 at 7:23pm

physics
If you weigh 650 N on the earth, what would be your weight on the surface of a neutron star that has the same mass as our sun and a diameter of 15.0 km ? Take the mass of the sun to be ms = 1.99×10^30 kg, the gravitational constant to be G = 6.67×10^−11 Nxm^2...
Thursday, March 29, 2012 at 1:53pm

Physics -please help
This is for my earth science class I have not had physics- If a person pulls on a cart to the right with a force of 10 N and a second person pulls to the left with a force of 3 N, what is the net force(+direction)on the cart? I came up with 130 N downward force
Thursday, March 29, 2012 at 9:56am

Science
The sun emits billions of watts of light,heat,and energy ever second. How much of this light,heat, and energy does the Earth benefit from?
Wednesday, March 28, 2012 at 9:54pm

physics
The weight of the atmosphere above 1 m^2 of Earth's surface is about 100,000 N. Density, of course, becomes less with altitude. But suppose the density of air were a constant 1.2 kg/m/s^3. Calculate where the top of the atmosphere would be.
Wednesday, March 28, 2012 at 7:41pm

ms. sue
ms. sue only one story be due today and i do questions myself for that one but this one i need help you please help me? this be emily carr story d'sonoqua D’Sonoqua I was sketching in a remote Indian village when I first saw her. The village was one of those that the ...
Wednesday, March 28, 2012 at 7:21pm

Astronomy
You've been told the Earth puts out 0.070 [W/m squared] as a global average. What would you predict would be the surface heat flux in [W/m squared] from a planet that is 70% larger in radius than the Earth, but has the same bulk composition. You can assume the only source ...
Wednesday, March 28, 2012 at 6:36pm

Astronomy
When the Sun ends up as a white dwarf, billions of years from now, it will contain about 40 percent of its present-day mass and have the same radius as Earth. What will be its density? How many times more dense is that than the present-day Sun?
Wednesday, March 28, 2012 at 7:16am

English
this be emily carr story d'sonoqua D’Sonoqua I was sketching in a remote Indian village when I first saw her. The village was one of those that the Indians use only for a few months in each year; the rest of the time it stands empty and desolate. I went there in one ...
Tuesday, March 27, 2012 at 8:50pm

Astro
Suppose you lived on a planet with the same radius as the Earth, but it had a density 2.99 times Earth's density. Your weight would be different on this planet. Find how much you would weigh on this planet divided by your weight on Earth
Tuesday, March 27, 2012 at 5:49pm

physics please help!!
A distant galaxy is simultaneously rotating and receding from the earth. As the drawing shows, the galactic center is receding from the earth at a relative speed of uG = 1.90 106 m/s. Relative to the center, the tangential speed is vT = 3.00 105 m/s for locations A and B, ...
Tuesday, March 27, 2012 at 2:38am

physics please help!!
A distant galaxy is simultaneously rotating and receding from the earth. As the drawing shows, the galactic center is receding from the earth at a relative speed of uG = 1.90 106 m/s. Relative to the center, the tangential speed is vT = 3.00 105 m/s for locations A and B, ...
Tuesday, March 27, 2012 at 2:36am

physics
How might you determine the age of a star from an Earth-based telescope? What measurements might you make?
Monday, March 26, 2012 at 12:13pm

earth
3. Show how the length of day changes with latitude by plotting the following points. Use the table below as a graph and place an X in the box where you want to plot a data point. For example, if you find that a day is 10 hours long at 30° N latitude, represent this data ...
Monday, March 26, 2012 at 6:08am

math
The space station is going 17500 mph as it orbits the earth. How long will it take to orbit 1 time if the earths diameter is 7926 miles and the space station orbits at 240 miles above the earth.
Sunday, March 25, 2012 at 2:29pm

physics
The difference between energy radiated from the sun and energy radiated from the Earth has to do with ____________________. A) Neither of these.B) Both of these.C) radiation frequencies.D) the amounts of radiant energy.
Sunday, March 25, 2012 at 2:02pm

physics
The difference between energy radiated from the sun and energy radiated from the Earth has to do with ____________________. A) Neither of these.B) Both of these.C) radiation frequencies.D) the amounts of radiant energy.
Saturday, March 24, 2012 at 9:44pm

physics
Which of these two bodies gets its internal heat from nuclear processes? A) Both.B) Sun.C) Neither.D) Earth.
Saturday, March 24, 2012 at 9:44pm

english ~ poems
America by James Monroe Whitfield "America, it is to thee, Thou boasted land of liberty,— It is to thee I raise my song, Thou land of blood, and crime, and wrong. It is to thee, my native land, From whence has issued many a band To tear the black man from his soil, ...
Saturday, March 24, 2012 at 5:03pm

NCSU
A man of mass 83.5 kg walks down the aisle of an airplane at a speed of 1.60 m/s in the forward direction while the plane moves at a speed of 295 m/s relative to the earth. (a) Find the man's kinetic energy relative to the plane. (b) Find the man's kinetic energy ...
Saturday, March 24, 2012 at 4:47pm

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