Explain the steps of the life cycle of a star. Beginning with a nebula and ending with old age/death of a star, explain each step in a star’s life cycle

Answers

Answer 1
Gas Clouds (of Hydrogen), starts contracting under the influence of gravitational pull of gas.

As it's contracting, it's pressure & temperature increases, it is called "Protostar" now.

When Temperature become sufficiently high (4 million C), Nuclear fusion starts, & large amount of energy releases.

Energy Travels to star's surface and is radiated in the form of light, heat & EM Radiation.

The contraction of star stops only when "Inward Gravitational pull" is balanced by "Outward Radiant Energy". At this time, star becomes stable in size & temperature.

Contraction continues, 'causes star's outer region to 'boil' & 'expand'. At this stage, it becomes brightest, red giant.

As fuel burns, helium nuclei fuses & form Carbon nuclei further to silicon & further to Iron Nuclei by progressive Nuclear Fusions. At all this stages, star was very unstable.

Star end it's life in many different way & it depends on it's mass, whether it ends as "White Dwarf", "Neutron Star" or "Supernova"

This was a short note on life story of star. Hope this helps!
Answer 2

Final answer:

The life cycle of a star begins in a nebula and can end as a white dwarf, neutron star, or black hole, depending on its mass. The main sequence and red giant phases are critical stages in a star's evolution.

Explanation:

The life cycle of a star is a fascinating journey from birth to death, marked by transformations driven by nuclear processes and the gravitational pull. Understanding this cycle offers insights into the transient nature of celestial bodies and the forces shaping our universe.

Birth in a Nebula

Stars begin their lives in nebulae, massive clouds of gas and dust. Over millions of years, these clouds contract under gravity, heating up the core until nuclear fusion starts, marking the birth of a new star.

Main Sequence Stars

Once a star begins fusing hydrogen into helium in its core, it enters the main sequence phase, which can last billions of years, depending on its mass. Our Sun is currently halfway through this stage, expected to last a total of about 10 billion years.

Red Giant

As a star exhausts its hydrogen fuel, it expands into a red giant. For a Sun-like star, this phase will see it swell significantly, engulfing nearby planets.

Planetary Nebula and White Dwarf

Eventually, the outer layers of the red giant are ejected, leaving behind a planetary nebula. The core that remains cools and contracts into a white dwarf, marking the end of its life cycle. For stars like our Sun, this white dwarf will slowly fade over billions of years.

Massive Stars' Fate

Larger stars may undergo more dramatic endings, including supernova explosions, leaving behind neutron stars or black holes, depending on their mass.


Related Questions

An airplane is heading due south at a speed of 600 km h. If a wind begins blowing from the
southwest at a speed of 100 km h (average), calculate: (a) the velocity (magnitude and direction) of the plane relative to the ground ...?

Answers

Final answer:

To calculate the velocity of the plane relative to the ground, add up the x and y components of the plane's velocity and the wind velocity. Find the magnitude and direction of the resultant velocity using the Pythagorean theorem and trigonometry.

Explanation:

To calculate the velocity of the plane relative to the ground, we need to consider the vector sum of the plane's velocity and the wind velocity. We can break down the velocity vectors into their x and y components. The plane's velocity is due south, so its x component is 0 km/h and its y component is -600 km/h. The wind velocity is blowing from the southwest, which can be represented as 45 degrees south of west. Its x component is -100*cos(45) km/h and its y component is -100*sin(45) km/h. Now we can add up the x and y components to find the resultant velocity vector. The x component is 0 + (-100*cos(45)) km/h and the y component is -600 + (-100*sin(45)) km/h. Finally, we can find the magnitude and direction of the resultant velocity vector using the Pythagorean theorem and trigonometry. The magnitude is sqrt(x^2 + y^2) km/h and the direction can be found using the arctan(y/x) function.

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The stars and planets are made of _______.
A. dark energy
B. dark matter
C. baryonic material

Answers

It's obvious that the stars and planets are made of C. baryonic material. As it's madef of elements which are made of molecules.

You plan a car trip for which you want to average 90 km/h. You cover the first half of the distance at an average speed of only 48 km/h. What must your average speed be in the second half of the trip to meet your goal?

Answers

Final answer:

The average speed for the second half of the trip needs to be 90 km/h.

Explanation:

To find the average speed you need to consider the total distance and total time.

In this case, let's assume the total distance is d kilometers. So, the first half of the distance is d/2 kilometers.

The first half is covered at an average speed of 48 km/h, which means it takes (d/2) / 48 hours to cover the first half.

To meet the goal of averaging 90 km/h for the entire trip, the average speed for the second half needs to be enough to cover the remaining distance (d/2) with the remaining time (d/2) / 90 hours.

Therefore, the average speed for the second half of the trip needs to be 90 km/h.

Which of these is a source of voltage?
a. a battery
b. a generator
c. an electrical outlet
d. all of these are voltage sources.

Answers

D, all of these are voltage sources. A battery can power small things, generators can power larger things, and outlets can charge, or power things.
the answer is all the Above.

A laser produces 20.0 mW of red light. In 1 hour, the laser emits 2.29 X 10^20 photons. What is the wavelength of the laser?

Answers

Using Planck's equation,

E = nhc / λ

Also, Power = Energy / time
E = 20 x 10⁻³ x 60 x 60
E = 108 J

108 = (2.29 x 10²⁰ x 6.63 x 10⁻³⁴ x 3 x 10⁸) / λ
λ = 4.22 x 10⁻⁷ m

A high school physics student is sitting in a seat reading this question. The magnitude of the force with which the seat is pushing up on the student to support him is closest to what?

Answers

The force pushing down  is the force of Gravity. On a chair it is in perfect balance with the force pushing up (the normal force)
 

in terms of magnitude 
FN = FG = mg

the forces are in opposite direction

hope this helps

Answer:

Force due to seat must be equal to the Weight of the student

Explanation:

As we know that the student is sitting on the seat at rest

So here we can say that at this position the student must be at equilibrium position

so we can write force equation for this position of student

vertically downward the net force is due to his/ her weight which is given as

[tex]W = mg[/tex]

now this weight of the student is counter balanced by the the normal force due to seat which is in opposite direction

Now for equilibrium position of the object we will have

[tex]F_n = mg[/tex]

so the seat will push the student upwards by force which is equal to the weight.

Crystals can have _____ bonds between their atoms.
ionic
covalent
metallic
all types of

Answers

Answer;

All types of

Crystals can have all types of  bonds between their atoms.

Explanation;Crystals are solid materials which contains atoms, molecules or ions that are arranged in a complex structure forming a crystal lattice.Crystals may have all types of bonds, these includes; ionic bonds, formed as a result of transfer between a metallic bond and a non-metal atom, Covalent bond, formed as a result of sharing electrons between non metal atoms, hydrogen bonds, metallic bonds Van der Waals bonds, etc.

If a constant force acts on two objects of different masses, which object will accelerate more?
a. the larger object
c. both objects will respond in the same way
b. the smaller object
d. the larger object will speed up, but the smaller object will slow down

Answers

the answer a bc m/v=a

Answer:

b. the smaller object

Explanation:

According to Newton's second law, when a force is applied to an object, it accelerates. This acceleration is proportional to the intensity of the applied force and is inversely proportional to the mass that moves. Therefore, the lower the mass, the greater the acceleration.

A girl delivering newspapers covers her route by traveling 2.00 blocks west, 3.00 blocks north, and then 7.00 blocks east.

(a) What is her resultant displacement?
____blocks at ____° north of east

(b) What is the total distance she travels?
____blocks ...?

Answers

she travels 2+3+7 blocks for a total of 12 blocks  (B part)
So she travels √(5^2+3^2) = √34 blocks part(A)

ATP molecules store cellular energy. When phosphate groups are removed and molecules of ADP are formed, energy is released. This energy can be used to perform


...?

Answers

Final answer:

The energy released from ATP molecules breaking down into ADP is used for various cellular functions like muscle contraction, transportation of substances, synthesis of biological molecules, and maintaining body temperature.

Explanation:

When ATP molecules break down into ADP (adenosine diphosphate), the process releases energy. This energy finds use in various cellular functions, including muscle contraction, active transport of substances across cell membranes, synthesis of biological molecules, and maintaining body temperature. Essentially, an ATP molecule releases energy when it loses a phosphate group, and this energy powers biological processes requiring energy inside a cell.

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ATP molecules store energy that is released when converted to ADP and is used to perform cellular work. This energy is essential for processes such as muscle contraction and active transport in cells. The correct answer is D. cellular work.

ATP molecules play a crucial role in storing and providing energy for cellular work.

When ATP is broken down into ADP and an inorganic phosphate, energy is released and can be used for various cellular processes. This energy release is critical for activities like muscle contraction, active transport in cell membranes, and chemical reactions within the cell.For example, in muscle cells, the energy from ATP is used to move contractile proteins that enable muscle contraction. In cellular transport, ATP is vital for the function of the sodium-potassium pump, which maintains the cell's electrochemical gradient by actively transporting ions against their gradients.

Correct answer is D. cellular work.

complete question:

ATP molecules store cellular energy. When phosphate groups are removed and molecules of ADP are formed energy is released. This energy can be used to perform?

A. osmosis

B. electron transport

C. diffusion

D. cellular work

How Close to the edge of a 20kg table, can a 66kg person sit without tipping it over?
The table is 2.2m long and there are two legs placed 0.5 m from each end of the table. with 1.2 meters between the two legs. the top of the table is 0.80 m tall

Answers

m1d1=m2d2
because gravity is constant to both side. Calculate the mass per length of the table, and find the amount of weight for one side of the leg and then multiply it by the length, which is 1.7m. The divide the product by the mass of the guy to get the length from the table.
and the answer is 0.3981m.

Answer:

0.318 m

Explanation:

If the moment due to the person’s weight is equal to the moment due to weight of table, table will not tip over.

Moment due to table = Moment due to person         ………… (i)

Moment due to table = (20)(9.8)(0.6) = 117.6 Nm

Moment due to person = (66)(9.8)(0.5-x) = 323.4 – 646.8x Nm

Where, x is the distance of person from the edge.

By putting values in equation (i),

117.6 = 323.4 – 646.8x

solving for x,

x = 0.318 m

an object is in circular motion. how will the object behave if the centripetal force is removed?

a . it would move in a line away from the circle

B. it would move in a line toward the circles center

C. it would move in a curbed , circular path

B. it would move in a line tangent to the circular path

Answers

You have two choices with the same letter. The correct choice is the last one ... Move along a tangent.

The correct answer is

B. it would move in a line tangent to the circular path

In fact, the centripetal force is the only force that keeps the object in a circular trajectory, pulling the object towards the centre of the circle. When this force is removed, there are no other forces acting on the object, therefore for the law of inertia, the object will continue to move at constant velocity, therefore in the same direction (tangent to the circular path) at constant speed.

It is important to maintain septic systems in order to

Answers

It is important to maintain septic systems in order to prevent untreated sewage from contaminating groundwater

If a loaded truck that can accelerate at 2 m/s2 loses its load and has one-third of its original mass, what acceleration can it attain if the same driving force acts on it?

Answers

m* 2m/s^2 = 1/3 m * a

2m/s^2  = 1/3 a (multiply other side by 3)

2m/s^2 * 3=  a

= 6 m/s^2

Hope this helps

Answer:

a₂ = 6 m/s²

Explanation:

Conceptual Analysis

We apply Newton's second law:

F=m*a Formula (1)

m: mass  in kilograms (kg)

a: acceleration (m/s²)

F: force in Newtons (N)

Known Data

a₁ = 2 m/s²

m₁= m

m₂= (1/3)m

Problem development

We apply formula (1) for the two conditions given:

F₁ = m₁*a₁ = m*2

F₂ = m₂*a₂= (1/3)m*a₂

F₁ = F₂

m*2 =  (1/3)m*a₂   We divide by m on both sides of the equation

2 = (1/3)*a₂

6 = a₂

a₂ = 6 m/s²

The distance "d" you bike varies directly with the amount of time "t" you bike. Suppose you bike 13.2 miles in 1.25 hours. What is an equation that relates "d" and "t"? What is the graph of the equation? ...?

Answers

Final answer:

The equation relating distance "d" and time "t" is d = 10.56t. This equation represents a direct variation between distance and time, where 10.56 is the constant of variation. The graph of this equation is a straight line passing through points (0,0) and (1.25, 13.2).

Explanation:

The distance "d" you bike varying directly with the amount of time "t" you bike suggests a linear relationship. This can be represented as d = kt, where "k" is the constant of variation, representing the rate you bike per hour. From the provided information, we know that if you bike for 1.25 hours, you travel 13.2 miles. That means k = d/t = 13.2 / 1.25 , which equals 10.56. So the equation relating "d" and "t" is d = 10.56t.

To graph this equation, you would plot time on the x-axis and distance on the y-axis. Begin by plotting a point at (0,0). Then plot a second point at (1.25, 13.2) as given. Draw a line through these points. The slope of this line is 10.56, which verifies our equation. This:

Displays direct variationShows distance traveled over timerepresents the equation d = 10.56t

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The ice in his drink has a mass of 6 g and a volume of 20 cm3. what is the density of the ice?

Answers

I'm pretty sure 0.3 is the answer. Because P(density) = m/V  

he graph below shows the velocity f(t) of a runner during a certain time interval:

graph of line going through ordered pairs 0, 4 and 4, 8. Graph of another line going through ordered pairs 4, 8 and 8, 0. Label on the x axis is time in second and label on the y axis is velocity in meter per second

Which of the following describes the intercepts on the graph?

The initial velocity of the runner was 4 m/s, and the runner stopped after 8 seconds.
The initial velocity of the runner was 8 m/s, and the runner stopped after 4 seconds.
The initial acceleration of the runner was 4 m/s2,

Answers

Answer is "the initial velocity of the runner was 4 m/s, and the runner stopped after 8 seconds".

This is a velocity - time graph

At t = 0 s, the graph has a velocity as 4 m/s. This means, the runner has an initial velocity as 4 m/s

At t = 4 s, the runner has reached his maximum velocity as 8 m/s and acceleration is 1 m/s².

After t = 4 s, the velocity has decreased with the time means it is a negative acceleration

At t = 8 s, the velocity of the runner has reached to zero means runner has stopped after 8 seconds.

Which of the following is the best definition of an isotope?
A. elements of the same kind with different numbers of neutrons
B. elements of the same kind that have lost electrons
C. elements of the same kind that have different electrical charges
...?

Answers

The best and most correct answer among the choices provided by your question is the first choice or letter A.

Isotopes are elements of the same kind with different numbers of neutrons.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!

Answer:

A. elements of the same kind with different numbers of neutrons

Explanation:

As we know that an atom is represented by

[tex]_z^AX[/tex]

here we know that

z = atomic number

A = atomic number + number of neutrons

now if the number of neutrons in an atom is different but having same number  atomic number then the combination of such group of atoms is known as isotopes.

So here we have

[tex]_z^{A_1}X, _z^{A_2}X[/tex]

so above is the example of isotopes

A barometer is used to measure air pressure. true or false.

Answers

the answer is "True" .

Answer:

true

Explanation:

edge 2021

what force is needed to give a 0.25-kg arrow an acceleration of 196 m/s^2A. 0.25 NB. 49 NC. 748 ND. 196 N

Answers

We Know, F = m*a
Here, m = 0.25 Kg
a = 196 m/s²

Substitute it into the expression, 
F = 0.25*196
F = 49 N

So, option B is your final answer.

Hope this helps!

F = 49N

I Took The Test!

does centripetal force change in uniform circular motion?

Answers

it depends on how fast you are going and in orincipal no

The centripetal force in uniform circular motion remains constant as long as the object's mass and velocity don't change, since centripetal force is calculated as the mass times centripetal acceleration (Fc = mac).

In uniform circular motion, the centripetal force must remain constant to maintain the motion. The second law of motion given by Newton states that net force is mass times acceleration: net F = ma. We have centripetal acceleration (a = ac) for uniform circular motion, and consequently, Fc, the magnitude of centripetal force is Fc = mac. This equation implies that as long as the mass of the object and its velocity (which together determine ac) remain constant, the centripetal force will also remain constant. It is this force that maintains the object in a circular path, acting towards the center of curvature and altering the direction of the object without changing its speed.

It's important to note that centripetal force is not a particular type of force; rather, it could be provided by any force or combination of forces that act towards the center of the object's circular path, like gravitational force, tension, friction, or any other appropriate force that can cause the required centripetal acceleration for uniform circular motion.

The electromagnetic waves that have the lowest frequency is called

Answers

Radar waves are the waves with the lowest energy.

The electron configuration of an element is 1s22s22p63s23p64s1. Why is this a REPRESENTATIVE element?

Answers

the highest s-orbital or p-orbital is practically filled

Answer:

D) The highest s-orbital or p-orbital is partially filled.

Explanation:

The element with electronic configuration The electronic configuration of an element is 1s22s22p63s23p64s1 has a partially filled s-orbital. This is typical of a representative element. In a representative element the highest s-orbital or p-orbital is partially filled.

What does the physics equation EF=0 mean?

Answers

The sum of all the forces acting on an object is zero. That means the object is in equilibrium, not experiencing an acceleration.

Equation ΣF=0 refers total force applied on the body is zero. The forces acting on a body are referred to as balanced forces when the sum of all the forces acting on the body equals zero.

What is force?

The definition of force in physics is: The push or pull on a massed object changes its velocity.

An external force is an agent that has the power to alter the resting or moving condition of a body. It has a direction and a magnitude. The application of force is the location at which force is applied, and the direction in which the force is applied is known as the direction of the force.

Equation ΣF=0 refers total force applied on the body is zero.

The forces acting on a body are referred to as balanced forces when the sum of all the forces acting on the body equals zero.

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Your question is incomplete. But most probably, the question was:

What does the physics equation ΣF=0 mean?

Explain the difference between the degree measure of an arc and its arc length ...?

Answers

The degree measure tells you how many degrees around a circle it goes; its length is how long it would be if straightened out. Like all semicircles have degree measure 180 no matter how big the circle they came from is.


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A blank is any disturbance that carries energy from one place to another through matter and space.

Answers

Answer;

A wave

A wave is any form of a disturbance that carries energy from one place to another through a matter and space

Explanation;Waves carry energy from one point, the source to another point or place. The transmission of a wave may occur through the space or through a material medium. Electromagnetic waves are those waves whose transmissions occurs through the space, they do not require material medium for transmission,for example, radio waves, while mechanical waves are those that require material medium for transmission, for example sound waves.The energy of wave depends on the frequency of the wave and the wavelength of that particular wave.

Explanation:

A wave is a disturbance that carries energy from one place to another through matter and space.

When we through a stone or a pebble in calm water, then the particles of water moves up and down and this process continues for some time. This implies that there is a disturbance produced in water.

The wave can be described using second-order linear partial differential equation. It is termed as wave equation.

There are many types of waves like the transverse wave and the longitudinal waves.

The height, h, of a falling object t seconds after it is dropped from a platform 300 feet above the ground is modeled by the function h(t)=300-16t^2 Which expression could be used to determine the average rate at which the object falls during the first 3 seconds of its fall?

A.) h(3) – h(0)
B.) h(3/3)-h(0/3)
C.) h(3)/3
D.) (h(3)-h(0))/3

Answers

The average rate at which the object falls during the first 3 seconds of its fall is [tex]\frac{h(3) - h(0)}{3}[/tex].

Model of the object's motion

The function of the object's motion is given as h(t) = 300 - 16t².

Velocity of the object after 3 seconds

The velocity at which the object falls during the first 3 seconds of its fall is calculated as follows;

[tex]v = \frac{dh(t)}{dt} = -32t[/tex]

Average rate

The average rate of the motion is calculated as follows;

[tex]v = \frac{h(3) - h(0)}{3}[/tex]

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Answer:

D

Explanation:

Jack tries to place magnets on the door of his refrigerator. He observes that the magnets don’t stick. He guesses that the door of the refrigerator is made of a nonmagnetic substance. What stage of scientific investigation does his guess represent?

Answers

I think an education guess for this one because he is thinking about what to guess probably.

Answer:

Constructing a Hypothesis

Explanation:

Jack already made his observation (magnet doesnt stick).  After that Jack then guesses that the fridge was made of nonmagnetic substance.  Now he must construct a hypotesis.

If a 60-watt bulb is used to light a room, how much current is flowing through the bulb given that the voltage is 120 volts?

Answers

 Well, if I understand correctly, I think it'd be 60, because 60+60= 120, but I may be wrong. It's not my best subject, but why not try to help even though I suck lol.  

The current flowing through a 60-watt bulb with a voltage supply of 120 volts is calculated using the equation I = P/V, which yields a result of 0.5 amperes.

To calculate the current flowing through a 60-watt bulb given a voltage of 120 volts, we can use Ohm's Law and the power equation. The power equation is P = IV, where P is power in watts, I is current in amperes, and V is voltage in volts.

First, we need to rearrange the equation to solve for the current I. Doing so, we get I = P/V. By substituting the given values, we have I = 60 W / 120 V. Therefore, I = 0.5 A.

The result shows that a current of 0.5 amperes (0.5 A) is flowing through the 60-watt bulb when it is connected to a 120-volt power supply.

In which situation would you see a partial lunar eclipse ?
A.the entire moon passes through earth shadow
B.the moon passes between earth and the sun
C.a portion of the moon passes through earths shadow
D.the moon lies completely outside of earths shadow

Answers

C.a portion of the moon passes through earths shadow....


Answer: The correct answer is Option C.

Explanation:

Lunar eclipse is defined as the condition which arises when moon passes behind Earth to its shadow.

Partial lunar eclipse arises when a portion of moon passes through Earth to its shadow and total lunar eclipse arises when moon passes directly behind Earth's shadow.

Hence, the correct answer is Option C.

Other Questions
Which is the better deal?1 pack of paper for $2.502 packs for $4.003 packs for $6.504 packs for $10.00 And indeed there will be timeFor the yellow smoke that slides along the street,Rubbing its back upon the window panes;There will be time, there will be timeTo prepare a face to meet the faces that you meet;There will be time to murder and create,And time for all the works and days of handsThat lift and drop a question on your plate;Which phrase from the excerpt most clearly conveys the speaker's leisurely tone? Yteermbath...arrange those words Publishers often add _____ to a text to help readers understand the meaning of old words. Determine the zeros of x^2 + 4x - 16 = -2x . How does the army surgeon feel about this winter at Valley Forge? What is the description of one-hundredth of 36? Ralph is 3 times as old as Sara. In 6 years, Ralph will be only twice as old as Sara will be then. Find Ralph's age now. Ralph's age is _____. A)6 B)12 C)18 D)24 Is the following definition of supplementary reversible? If yes, write it as a true biconditional . Linear pairs of angles are supplementary. A. The statement is not reversible B. Yes, if angles form a linear pair, they are supplementaryC. Yes, angles form a linear pair if ( and only if ) they are supplementary D. Yes, angles are supplementary if they form a linear pair You can still go to work, although you should not work with food or in food preparation areas, if you have which of the following illnesses?a. Hepatitis Ab. Shigellosisc. Typhoid Feverd. The common cold The production of four haploid gametes from one mother cell is completed during For the following system.kx + y + z = 1x + ky + z = 1x+ y + kz = 1Determine for what values of k the system has:a) No solutionsb) One solutionc) A lot of solutions ...? Which is a major cause of European exploration ?A.the need to reduce Europe's population B. A desire for direct access to spice's C.the need to limit the growth of Arab empires D. A desire for better fishing grounds Similarities between Judaism and Islam What major problems did the South experience in fighting and winning the war? Southern black troops staged countless mutinies. African American slaves burned several southern cities. It lacked enough food, effective transportation, and military hardware. There was incessant meddling in its affairs by France and England. Why was hammurabi's code of 199 unfair? if a man puts out the eye of a slave, he shall pay half the slave's price. a grocery store ordes 47 bags of onions and 162 bags of potatoes. the onions cost $2 per bag, and the potatoes cost $3 per bag. how much is spent on onions and potatoes? On an airplane, there are two seats on the left side in each row and three seats on the right side. There are 150 seats altogether. How many seats are on the left side of the plane and how many are on the right? Apply the rules for order of operations to simplify 2+3-4+(5X4) #1: Which mountains separate European Russia from Asian Russia?A. CaucasusB. Zagros C. Lena D. Ural