Wednesday
July 29, 2015

Homework Help: Science: Earth

Recent Homework Questions About Earth

Earth Science to Ms.Sue (urgent )
18.   The Cenozoic Era is also referred to as the  A. Age of Dinosaurs. B. Age of Mammals. C. Age of Fish. D. First Era. B???
Tuesday, February 24, 2015 by Sarah

Earth Science to Ms.Sue
9.   Another name for unicellular organisms that dominated Earth up to the Precambrian time is  A. eukaryotes. B. cyanobacteria. C. stromatolites. D. prokaryotes. D?
Tuesday, February 24, 2015 by Sarah

Earth Science
Why does the Earth have a magnetic field?
Tuesday, February 24, 2015 by Alexgc

physics
Calculate the distance between the center of the earth and the center of the moon at which the gravitational force exerted by the earth on an object is equal in magnitude to the force exerted by the moon on the object.
Monday, February 23, 2015 by Cali

physics
A satellite is in a circular orbit around the Earth at an altitude of 3.30 106 m. (a) Find the period of the orbit. (Hint: Modify Kepler's third law so it is suitable for objects orbiting the Earth rather than the Sun. The radius of the Earth is 6.38 106 m, and the mass of...
Sunday, February 22, 2015 by alba

physics
After the Sun exhausts its nuclear fuel, its ultimate fate may be to collapse to a white dwarf state. In this state, it would have approximately the same mass as it has now, but its radius would be equal to the radius of the Earth. (a) Calculate the average density of the ...
Sunday, February 22, 2015 by alba

Earth Science
4.   Ancient cyanobacteria released ______, which assisted in creating the atmosphere as we know it today.  A. oxygen B. lead C. hydrogen D. ore A?
Sunday, February 22, 2015 by Sarah

math
A vector can be used to represent the path of a drill tip used to bore a deep mine shaft in Sudbury one quarter of the way to the centre of the Earth. Represent the vector using a directed line segment and Cartesian co-ordinates and describe which representation may be more ...
Saturday, February 21, 2015 by anon

physics
If a person weighs 700N on Earth, what force due to gravity would they exert on a 1500kg car they are standing 1.5m from? Assume the distance is between their centres of mass. F=Gm1xm2/r^2?
Friday, February 20, 2015 by Emma

Overdue Science Lesson, Very Urgent.
1: How does sea-floor spreading occur? A, New materials are being added to the asthenosphere. B, Earthquakes break apart the ocean floor. C, Sediments accumulate at the area of spreading. D, Molten material beneath Earth's crust rises to the surface. 2, Which features form...
Friday, February 20, 2015 by Anonymous :)!

physics
The magnetic field of the Earth is 0.50 x 10-4 T in a certain location. a) What will be in Newtons the force on a completely ionized carbon atom (Z = 6, A = 12) traveling with the solar wind with a velocity of 18.00 x 103 m/s perpendicular to the magnetic field? b) How fast ...
Friday, February 20, 2015 by Trisha

physics
A 25,000 kg rocket ship near the surface of the Earth accelerates upwards due to a constant 1.25 MN of thrust from its engine. A simple pendulum on the ship is observed to complete 100 full swings in 75.0 s. What is the length of the string? 1. For a simple pendulum: T = 2&#...
Friday, February 20, 2015 by Anonymous

PHYSICS
A hypothetical planet has a mass 1.55 times that of Earth, but the same radius. What is g near its surface?
Friday, February 20, 2015 by Natalie

Algebra 1
Earth has a radius of about 6.4 x 10 to the 6th power m. Approximate the surface area of earth using the formula for the surface area is a sphere, S = 4 pi r squared. Earths surface is about 70 percent water. About how many square meters of earths surface are covered with ...
Thursday, February 19, 2015 by Lauren

physics
The magnetic field of the Earth is 0.60 x 10-4 T in a certain location. a) What will be in Newtons the force on a completely ionized carbon atom (Z = 6, A = 12) traveling with the solar wind with a velocity of 10.50 x 103 m/s perpendicular to the magnetic field? b) How fast ...
Thursday, February 19, 2015 by Annie

science
1. What would happen to an object if the force of gravity on Earth was decreased by half? (1 point) Its mass would decrease. Its weight would decrease.* Its density would decrease. Its volume would decrease. 2. Which of the following represents a heterogeneous mixture? (1 ...
Wednesday, February 18, 2015 by Oscar

physics
a pendulum is 0.75 meters long and has a period of 4.17seconds is this pendulum on the earth moon or mars?
Wednesday, February 18, 2015 by nikq

math
The Position of two A and B on the earth’s surface are (36°N, 49°E) and (360°N, 131°W ) respectively. (a) The difference in long between town A and town (b) Given that the radius of the earth is 6370, calculate the distance town A and town B. (c) Another ...
Tuesday, February 17, 2015 by kudu

physics
A woman with mass of 63 kg stands at the rim of a horizontal table having a moment of inertia of 520 kg m2 and a radius of 1.5 m. The turntable is initially at rest and is free to rotate about a frictionless, vertical axis through its center. The woman then starts walking ...
Monday, February 16, 2015 by Lexus

Accelerated Science
Match each situation with the correct method of heat transfer: a. radiation b. conduction c. convection __A_ 1) The inside of a car gets very hot when that car is parked on a parking lot in the middle of August. __A_ 2) During the winter when the furnace is running in a two-...
Monday, February 16, 2015 by Anonymous

Physics
A simple pendulum has mass 1.14 kg and length 0.760 m. (a) What is the period of the pendulum near the surface of Earth? (b) If the same mass is attached to a spring, what spring constant would result in the period of motion found in part (a)?
Sunday, February 15, 2015 by Joanna

Physics Circular Motion
A satellite in orbit around the earth has a period of one hour. An identical satellite is placed in an orbit having a radius that is nine times larger than that of the first satellite. What is the period of the second satellite?
Sunday, February 15, 2015 by Jayesh

Astronomy
The Hubble Space Telescope orbits at an altitude of 600 km above the Earth's surface. Assuming it is in a stable circular orbit, what is its velocity? For reference, the Earth's radius is 6400 km and Earth's mass is 6 x 10^24 kg. The formula to solve for circular ...
Sunday, February 15, 2015 by Allison

math
John was the first US astronaut to orbit Earth. His 3 orbit flight took 4 hours and 55 minutes. His spacecraft took off at 7:15 am. What time was John flight complete?
Sunday, February 15, 2015 by bryce

Earth Science
18.   Which of the following is a factor that determines the composition of magma?  A. Texture B. Elasticity C. Color D. Viscosity  D or B?
Saturday, February 14, 2015 by Sarah

Earth Science
16.   What type of instrument measures seismic waves?  A. Mercalli scale B. Seismic scale C. Seismogram D. Seismometer D?
Saturday, February 14, 2015 by Sarah

Earth Science
15.   _______ currents assist in the transfer of thermal energy from warmer climates to cooler climates.  A. Platonic B. Plutonium C. Convection D. Tectonic C? Please explain
Saturday, February 14, 2015 by Sarah

Earth Science
12.   The original location of an earthquake is also known as the  A. horizon. B. epicenter. C. hotspot. D. magnitude. B?
Saturday, February 14, 2015 by Sarah

Earth Science
11.   Which earthquake scale takes into consideration the damage caused by an earthquake?  A. Amplitude scale B. Moment magnitude scale C. Richter scale D. Modified Mercalli scale D?
Friday, February 13, 2015 by Sarah

Physics
The potential difference between a storm cloud and the ground is 2.13 × 108 V. If a bolt carrying 2 C falls from a cloud to Earth, what is the magnitude of the change of potential energy of the charge? Answer in units of J.
Friday, February 13, 2015 by Davie

Earth Science
5.   Most tornadoes carry wind speeds that range from  A. 105 to 177 km per hour. B. 178 to 266 km per hour. C. 267 to 322 km per hour. D. 1 to 105 km per hour. A?
Friday, February 13, 2015 by Sarah

Science
1. Which layer of the sun's atmosphere are you looking at when you look at an image of a sun? A) Photosphere B) Chromosphere C) Corona D) Prominence 2. What materials could have been found in a giant cloud that formed the solar system? A- hydrogen and helium B- hydrogen ...
Friday, February 13, 2015 by Katie

Earth Science
Could I have some help with the question down below?
Thursday, February 12, 2015 by Sarah

Earth Science
18.   How many chemical reactions are possible regarding the formation of carbonic acid and the dissolving of calcite?  A. 23 B. 10 C. 2 D. 3 I am stuck on this I looked in my text book and it shows the words but not the number answers!
Thursday, February 12, 2015 by Sarah

science
The flowerpot weighs 5 pounds on Earth and 0.29 pounds on Pluto. Which proportion could you use to calculate a 115-pound person’s weight on Pluto? A. 5 over 0.29 = 115 over w B. 0.29 over 5 = w over 115 C. 5 over 0.29 = w over 115 D. either A or B
Thursday, February 12, 2015 by Spartans

science
The same astronaut visited Pluto. His weight on Earth was still 170 pounds, and his weight on Pluto was only 10 pounds. He removed an ice core with a weight of 25 pounds on Pluto. What is the weight of the ice core on Earth? A. 1.5 pounds B. 15 pounds C. 42.5 pounds D. 425 pounds
Thursday, February 12, 2015 by Spartans

science
An astronaut who weighed 170 pounds on Earth found that his weight on Jupiter was 400 pounds. He captured an alien that weighed 120 pounds on Jupiter. What is the alien's weight on Earth? A. 34 pounds B. 51 pounds C. 78 pounds D. 283 pounds
Thursday, February 12, 2015 by Spartans

Physics
You are hitting a tennis ball against a wall. The 0.057-kg tennis ball traveling at 29 m/s strikes the wall and rebounds at the same speed. Earth is the object of reference. Determine the ball's change in momentum (magnitude).
Thursday, February 12, 2015 by Anonymous

Physics
When man stands on a bathroom scale here on Earth, it reads 560N . Assume each planet to be a perfect sphere with the following parameters. What would his mass be on Mars if Mars has a mass of 6.419 x 10^23 kg and a radius of 3.396 x10^6 m? and what is the magnitude of the ...
Thursday, February 12, 2015 by Derp

AP LIT
A VALEDICTION FORBIDDING MOURNING by John Donne As virtuous men pass mildly away, And whisper to their souls to go, Whilst some of their sad friends do say, "Now his breath goes," and some say, "No." So let us melt, and make no noise, [5] No tear-floods, ...
Thursday, February 12, 2015 by Sam Eaton

Science
Why are the days typically hotter in June than in December here in the US? D. Because the United States faces the sun in the summer and faces away from the sun in the winter E.Because the tilt of the Earth causes the sun's rays to be more concentrated in the summer due to ...
Wednesday, February 11, 2015 by M

Science
Why are the days typically hotter in June than in December here in the US? A.Beacuse the sun gives off more light and heat in the summer B.Because the Earth is closer to the sun in the summer and farther from the sun in the winter C.because the Earth's tilt causes the sun ...
Wednesday, February 11, 2015 by M

Chemistry
A 35.00 mL sample of water at 30.0°C is placed in an open container with an external pressure of 1.00 atm. 30.0 kJ of heat is added to the water sample. The density of water is 1 g/mL. (a) How many grams of liquid water remain at the end of the process? Like, the equation ...
Wednesday, February 11, 2015 by N

english
1 Four score and seven years ago, our fathers brought forth upon this continent a new nation: conceived in liberty, and dedicated to the proposition that all men are created equal. 2 Now we are engaged in a great civil war ... testing whether that nation, or any nation so ...
Tuesday, February 10, 2015 by amy626

physics
Is the charge on the surface of the earth due to an excess or a deficit of electrons?
Tuesday, February 10, 2015 by moooose

science
what type of eclipse would you expect to see if the moon passes directly between earth and the sun
Tuesday, February 10, 2015 by kamy

science
1) The force of gravity on the moon is 1/6 the force of gravity on earth. If you had a 1 kg box of cereal on earth which had a weight of 2.4 N, what would its mass be on the moon? why? 2) what is the volume of a textbook with dimensions 21.3 cm, 27.5 cm, 2.9 cm? please help me...
Monday, February 9, 2015 by kid

math
The position of two towns X and Y are given to the nearest degree as X(45° N, 10° W) and Y (45 N°, 70° W). Find (a) The distance between the two towns in (i) Kilometers ( take the radius of the earth as 63711) (ii) Nautical miles ( take I nautical mile to be 1....
Monday, February 9, 2015 by kudu

Physics
How do I find the recoil velocity of the earth immediately after the popper popped?
Monday, February 9, 2015 by Kim

Interior Design
please check my answers? Your client wants his dining room to be a cozy, dark, nighttime room where he can entertain just one or two people for casual, intimate dinners. The room won't be used during the day. The unfurnished room has a low seven-foot ceiling, two small ...
Sunday, February 8, 2015 by lila

science
i need help with a reason for the season science lab of how earth orbits sun
Sunday, February 8, 2015 by selina

physics (gravitation)
At what height above the surface of the earth does the acceleration due to gravity reduces by 64% .radius of earth 6400 km
Friday, February 6, 2015 by riya

Physics
Determine the ratio of Earth's gravitational force exerted on an 80-kg person when at Earth's surface and when 1000km above Earth's surface. The radius of Earth is 6370 km. I have tried (6370)^2/(7370)^2 = 0.747 and it is wrong??
Thursday, February 5, 2015 by Anonymous

Science
List some of the atmospheric conditions that might be described as weather? What is the purpose of weather on the earth?
Wednesday, February 4, 2015 by Daniela

English check
Read the following passage from the Odyssey: Tell me, where was it, now, you left your ship— around the point, or down the shore, I wonder?’ He thought he’d find out, but I saw through this, and answered with ready lie: Poseidon Lord, who sets the earth a-...
Wednesday, February 4, 2015 by Delia

physics
What is the net gravitational field due the sun and earth at the center of the moon? You are given that the mass of the sun in 1.99 x 10^30 and the mass of the earth is 5.97 x 10^24. The distance from the center of the sun to the center of the earth is 1.496 x 10^8 and the ...
Wednesday, February 4, 2015 by Brenda

Math
Polar ice is about 3/4 of the 3% of Earth's fresh water. What fraction of all of Earth's water is polar ice?
Tuesday, February 3, 2015 by Mo

Earth Science
1.   What term is used to describe the process by which agents are carried from one place to another because of erosion?  A. Disposition B. Deposition C. Reposition D. Transplantation B?
Tuesday, February 3, 2015 by Sarah

Physics
An Earth satellite moves in a circular orbit 946 km above Earth's surface with a period of 103.8 min. What are (a) the speed and (b) the magnitude of the centripetal acceleration of the satellite? I got an answer of 7388.897 m/s for part a, but I'm stuck on part b
Monday, February 2, 2015 by Amber

Physics
7. An early objection to the idea that the earth is spinning on its axis was that the earth would turn so fast at the equator that people would be thrown into space. Show the error in this logic by calculating the centripetal force needed to hold a 100. kg person in place at ...
Monday, February 2, 2015 by Brian

Physics
A 4.03-kg object is thrown vertically upward from the surface of Earth, where the acceleration due to gravity is g1 = 9.81 m/s2. The initial velocity is v1, and the object reaches a maximum height of y1. What is the maximum height, y2, if the object is thrown with a speed of ...
Monday, February 2, 2015 by Breauna

Language Arts
Which word best describes the tone of the following lines from "New World"? First Man, behold; the earth glitters with leaves; the sky glistens with rain. A. Appreciative B. Disgusted C. Puzzled D. Surprised Is the answer A? Thank you
Monday, February 2, 2015 by Callie

L.A.
To which sense do the following lines from "Grandma Ling" appeal? and there I faced my five foot height, sturdy legs and feet square forehead, high cheeks, and wide-set eyes A. hearing B.taste C. sight D. smell 2. which word best describes the tone of the following ...
Sunday, February 1, 2015 by Anonymous

chemistry
The figure shows a cube of air at pressure 1.0 atm above a hot surface on Earth. Contact with the hot surface causes the volume of the air to expand from 2.00 × 105 L to 2.20 × 105 L by the transfer of 8.2 × 106 J of heat. Assume the systems are isolated from...
Saturday, January 31, 2015 by Morgan

Physics
The space shuttle is in a 3e+5 m high orbit over the earth. The radius of the earth is 6.37e+6 m, the mass of the earth is 5.98e+24 kg. What is the distance from the center of the earth to the space shuttle? I don't know whether I would double the radius and the add the ...
Saturday, January 31, 2015 by Carly

Physics
An object in space is initially stationary relative to the Earth. Then, a force begins acting on the object, starting with a force of 0 N, and increasing at a uniform rate until the magnitude of the force is 56 N after the force has acted for 10 s. The body has a mass of 15 kg...
Friday, January 30, 2015 by Kev

reading
Scientists generally agree that Earth is getting warmer due to what's called the greenhouse effect. A greenhouse used for plants stays warm because sunlight and heat coming through the glass roof are mostly trapped. The heat doesn't radiate back into the atmosphere ...
Friday, January 30, 2015 by Anonymous

Physics
A 50 kg satellite circles the earth in an orbit with a period of 110 min. What minimum energy E is required to change the orbit to one with a period of 320 min? Assume both the initial and final orbits are circular. The Earth’s radius is 6.37 × 10^6 m, its mass is 5...
Friday, January 30, 2015 by Steven

Science
How would a geologist identify an igneous rock as intrusive? A. An intrusive rock has coarse grains because it cooled more slowly on the surface of the earth. B. An intrusive rock has coarse grains because it cooled more slowly beneath the surface of the earth.** C. An ...
Thursday, January 29, 2015 by Anonymous

Science
Earthquakes occur on the earth today, so we can assume they occurred in the past. Which important geologic principle does this sentence support? A. original horizontality B. faunal succession C. superposition D. uniformitarianism**
Thursday, January 29, 2015 by Anonymous

physics
CRITICAL THINKING: The term ”weight” in physics has the following very specific meaning: “The weight of an object is the name given to a particular force: the gravitational force exerted by the earth on the object, giving it an acceleration of 9.8 m/s2 near the ...
Thursday, January 29, 2015 by Anonymous

physics
CRITICAL THINKING: The term ”weight” in physics has the following very specific meaning: “The weight of an object is the name given to a particular force: the gravitational force exerted by the earth on the object, giving it an acceleration of 9.8 m/s2 near the ...
Thursday, January 29, 2015 by Anonymous

Science
Please could someone check these for me. 1In a series of rock layers, a geologist finds fossils of a lizard-like dinosaur and a fern-like tree in layers that are 1.0 m and 1.5 m deep. However, in a layer that is 2.0 m deep, he finds fossils of bony fish and shellfish. Which ...
Thursday, January 29, 2015 by Anonymous

Calculus
A hot air ballon lifts off the earth 300m away from an observer and rises straight up at a rate of 80m/min. At what rate is the angle of inclination of the observers line of sight increasing at the time the balloon is 300, above the ground?
Thursday, January 29, 2015 by Chris

physics
You fire a cannon ball from ground level at a speed of 20.0 m/s ∠30.0 Find the time taken for the ball to hit the earth. How far will it land?
Thursday, January 29, 2015 by axel

Earth Science to Ms.Sue
7.   What gives the gem amethyst its purplish color? A. Quartz B. Titanium C. Oxygen D. Iron The answer was not A, got this question wrong.
Wednesday, January 28, 2015 by Sarah

Earth Science
15.   Which statement best describes the composition of magma?      A. Magma is an element all its own.B. Magma contains the same elements as snow.C. Magma contains only three elements.D. Magma contains the same ...
Wednesday, January 28, 2015 by Sarah

Earth Science
   What element has 81 protons in the nuclei of its atoms?  A. Thallium B. Uranium C. Platinum D. Lead A?
Wednesday, January 28, 2015 by To Ms.Sue

Earth Science
Please check down below.
Wednesday, January 28, 2015 by To Ms.Sue

Earth Science
10.   Which statement best describes the formation of diamonds?  A. Diamonds form in kimberlites under very low pressure. B. Diamonds form in talc under very low pressure. C. Diamonds form in talc under very high pressure. D. ...
Wednesday, January 28, 2015 by Sarah

Earth Science
  A heterogeneous mixture is a  A. mixture in which its components retain their identity. B. component added to sand that makes it inseparable. C. mixture that always contains water. D. mixture in which its components can't be separated.&...
Wednesday, January 28, 2015 by Sarah

Science
I would really appreciate it if someone checked my answers and told me if they were right. Thx. ~Ashley 1. Which of the following determines the strength of the force of gravity between two objects? Check all that apply. A: The speeds of the objects. *B: The masses of the ...
Wednesday, January 28, 2015 by Xx_Ashley_xX

Earth Science
Describe how weathering and erosion can be both destructive or constructive. I am still confused on the difference of erosion and weathering...
Tuesday, January 27, 2015 by INeedHelp

Math
Needing help setting these problems up...not necesarily giving me the answers. thanks. In January 2009 the state of Nevada was facing a budget deficit of $1.5 billion. The population of the state was approximately 2 million. How much would each person in the state have to ...
Tuesday, January 27, 2015 by Ashley

Physics
What is the Earth's gravitational force on you when you are standing on the Earth and when you are riding in the Space Shuttle 380 km above the Earth's surface? Answer as a fraction of the surface gravity of Earth. (The Earth's radius is 6400 km.)
Tuesday, January 27, 2015 by Kayla

science
which one of earth's layers has the hottest temperature? why?
Monday, January 26, 2015 by patrisha

science
what is the weight on earth of an object that has a mass of 17kg?
Monday, January 26, 2015 by ashanti

physics
A ball is released from a hot air balloon moving downward with a velocity of -10.0 meters/second and a height of 1,000 meters. How long did it take the ball to reach the surface of Earth? Given: g = -9.8 meters/second2.
Monday, January 26, 2015 by tms

Physics
A 83.8 kg astronaut is working on the en- gines of a spaceship that is drifting through space with a constant velocity. The astronaut turns away to look at Earth and several sec- onds later is 39.6 m behind the ship, at rest relative to the spaceship. The only way to re- turn ...
Sunday, January 25, 2015 by Chris

physics
You're heading an international effort to save Earth from an asteroid heading toward us at 11km/s . Your team mounts a rocket on the asteroid and fires it for 10 min, after which the asteroid is moving at 21km/s at 32∘ to its original path. In a news conference, what...
Sunday, January 25, 2015 by Anonymous

physics
An 94.4 kg astronaut is working on the engines of a spaceship that is drifting through space with a constant velocity. The astronaut turns away to look at Earth and several seconds later is 29.6 m behind the ship, at rest relative to the spaceship. The only way to return to ...
Sunday, January 25, 2015 by Bri

english check
Treat the Earth and all that dwell thereon with respect. Remain close to the Great Spirit. Show great respect for your fellow beings. Work together for the benefit of all Mankind. Give assistance and kindness wherever needed. Do what you know to be right. Look after the well ...
Friday, January 23, 2015 by anon

earth
The radius of the Earth is approximately 3,960 miles. Find the approximate surface-area-to-volume ratio of the Earth.
Friday, January 23, 2015 by Anonymous

Science
1)What is the Theory of Plate Tectonics? 2)What physical features are caused by plate tectonics? 3)What causes Earth's plates to move continuously?
Friday, January 23, 2015 by Anonymous

english
Treat the Earth and all that dwell thereon with respect. Remain close to the Great Spirit. Show great respect for your fellow beings. Work together for the benefit of all Mankind. Give assistance and kindness wherever needed. Do what you know to be right. Look after the well ...
Friday, January 23, 2015 by anon

Orbital Mechanics
Some help with this exercise please. If you could give an explanation and not only the answers it would be great!!! Besides the 3-2-1 rotation sequence, another very common sequence in spacecraft applications is the 3-1-3 rotation sequence in which the z axis is used twice. ...
Friday, January 23, 2015 by ntae001

physics
A canoe has a velocity of 0.31m/s southeast relative to the earth. The canoe is on a river that is flowing
Thursday, January 22, 2015 by Anonymous

Triangles
How will you find the distance of a star from Sun, given that the angle at which it is viewed from the two solstices of Earth(i.e winter and summer) are alpha and beta respectively, and the distance between the points of the solstices is 150 million km. {Hint - form a triangle...
Thursday, January 22, 2015 by Shanu

Science
How does radioactivity make it possible to understand how Earth can be so old and still have a hot interior? (1 point) A.Radioactive elements trap heat from underground magma chambers. B.Radioactive elements absorb heat from the atmosphere and release it underground.*** C....
Wednesday, January 21, 2015 by jeje

True or False?
Sounds like an easy question but I just wanna be sure! :P Tides are caused by the force of inertia from the sun and moon acting on Earth. True or False? I think its false because its gravity not inertia.
Monday, January 19, 2015 by Bella

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Homework Help: Science

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