A pyramid was built with approximately 2.3 million stone blocks, each weighing 2.4 tons (1 ton = 2,000 lbm). Find the mass of the pyramid in kg.

Explanation:

The vector's direction is given by

\(\tan{\theta} = \dfrac{v_y}{v_x} = \dfrac{39\:\text{m/s}}{24\:\text{m/s}}\)

\(\:\:\:\:\:\:\:= 1.625\)

or

\(\theta = \tan^{-1}(1.625) = 58.4°\) with respect to the +x-axis.

From the calculations, the value of the acceleration due to gravity is 0.38 m/s^2.

The weight of an object is obtained as the product of the mass of the body and the acceleration due to gravity.

Thus;

When;

mass = 120 kg

weight =  46 N

acceleration due to gravity = 46 N/120 kg

=0.38 m/s^2

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Answer:

The density of the block is 1113.216 kilograms per cubic meter.

The weight of the block is 43669.237 newtons.

Explanation:

According to the Archimedes' Principle, the drag force experimented by the metal block is equal to the weight of the volume of water displace by the block. Besides, the block has a weight that cannot be neglected and experiments a tension from the cable. Given that the metal block is suspended, then we could consider that block is at rest.

From Newton's Laws of Motion we obtain the following equation of equilibrium:

\(\Sigma F = T-\rho_{m}\cdot V_{m}\cdot g + \rho_{w}\cdot V_{m}\cdot g = 0\) (1)

Where:

\(T\) - Tension on the cable, measured in newtons.

\(\rho_{w}\), \(\rho_{m}\) - Densities of salt water and the metal block, measured in kilograms per cubic meter.

\(V_{m}\) - Volume of the metal block, measured in cubic meters.

\(g\) - Gravitational acceleration, measured in meters per square second.

If we know that \(T = 42600\,N\), \(\rho_{w} = 1030\,\frac{kg}{m^{3}}\), \(V_{m} = 4\,m^{3}\), \(g = 9.807\,\frac{m}{s^{2}}\), then the density of the block is:

\(T+\rho_{w}\cdot V_{m}\cdot g = \rho_{m}\cdot V_{m}\cdot g\)

\(\rho_{m} = \frac{T+\rho_{w}\cdot V_{m}\cdot g}{V_{m}\cdot g}\)

\(\rho_{m} = \frac{42600\,N+\left(1030\,\frac{kg}{m^{3}} \right)\cdot (4\,m^{3})\cdot \left(9.807\,\frac{m}{s^{2}} \right)}{(4\,m^{3})\cdot \left(9.807\,\frac{m}{s^{2}} \right)}\)

\(\rho_{m} = 1113.216\,\frac{kg}{m^{3}}\)

The density of the block is 1113.216 kilograms per cubic meter.

Lastly, the weight of the block (\(W\)), measured in newtons:

\(W = \rho_{m}\cdot V_{m}\cdot g\) (2)

\(W = \left(1113.216\,\frac{kg}{m^{3}}\right)\cdot (4\,m^{3}) \cdot \left(9.807\,\frac{m}{s^{2}} \right)\)

\(W = 43669.237\,N\)

The weight of the block is 43669.237 newtons.

The arrow that represents the change of state of the substance is gaseous to liquid (O).

A change of state occurs when a matter gains or losses energy.

A liquid can change into solid or gas. A gas change into liquid or solid, depending on the average change in temperature.

The initial state of the substance is gas, because the atoms of the substance are far apart.

When the atoms are close together but are able to slide past one another, the state is liquid.

Note: atoms of solid substance are fixed.

Thus, the arrow that represents the change of state of the substance is gaseous to liquid (O).

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Considering the investigation and the observation made we can say the arrow that represents the change of state is: O

A change of state is the process by which a matter changes from one physical form to another.

in change of state we have mainly three states: Liquid, Gas and Solid.

Changing from gas to liquid is called condensation, because the atoms of gases move freely and faster. but once the speed reduces and their movement becomes restricted, then we say a condensation has occurred.

In conclusion, from the observation made, we can say the arrow that represents the change is Arrow O. which is from gas to liquid.

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Answer:Assuming, The new circuit is like the circuit attached below, the current in the new circuit will be 0.1 Ampere.

Explanation: Given, We have Potential Difference of 1.5V, Current of 0.05A.

Now, we know V = I x R ,where V is potential difference, I is current and R is resistance in the circuit.

∴ Putting the values ⇒ 1.5V = 0.05A x R

⇒R  =  1.5/0.05

∴R = 30 Ω

Now, It is said that A same identical wire is connected in parallel with the previous wire.

∴ New R will be ⇒ \(\frac{1}{R(new)}\) = \(\frac{1}{r} + \frac{1}{r}\)

=[1/30] + [1/30]

=1/15

∴ 1/R(new) = 15 Ω

Now, New Current in the circuit will be:

⇒ V= IR

⇒1.5V =  I x 15

⇒I = 0.1 A

Therefore, Answer will be 0.1 ampere.

The work W needed to stretch/compress a spring from rest by a distance x is

W = 1/2 kx²

where k is the spring constant.

This means the work needed to change the length of this spring by 10 cm = 0.01 m is

W = 1/2 (200 N/m) (0.01 m)² = 0.01 J

and by 15 cm = 0.015 m is

W' = 1/2 (200 N/m) (0.015 m)² = 0.0225 J

Then the total work performed on the spring by stretching from 10 cm to 15 cm is

∆W = W' - W = 0.0225 J - 0.01 J = 0.0125 J

Here are six things you can do to save energy or increase energy efficiency in any part of a house:

Install energy-efficient lighting and switch to LED lights from incandescent ones. While they live longer and consume up to 80% less energy than incandescent lights, LED bulbs require fewer replacements over time.

Upgrade your windows: Replace old windows with energy-efficient ones. Windows with double or triple panes, low-emissivity coatings, and insulated frames can significantly reduce heat loss in the winter and heat gain in the summer.

Install a programmable thermostat: A programmable thermostat allows you to set different temperatures for different times of the day, so you can automatically reduce heating or cooling when you're not at home or when you're sleeping.

Insulate your home: Adding insulation to walls, floors, and attics can help keep heat inside during the winter and outside during the summer, reducing your need for heating and cooling.

Upgrade to energy-efficient appliances: Energy-efficient appliances, such as refrigerators, dishwashers, and washing machines, use less energy and water than older models, which can help you save on your energy bills.

Seal air leaks: Seal air leaks around windows, doors, and other areas of your home to prevent drafts and heat loss. You can use weatherstripping, caulking, or other materials to seal gaps and cracks. This can help you save on heating and cooling costs and improve your overall energy efficiency.

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Answer:

more

hope this helps

plz mark brainliest

The special and general theories of relativity and Albert Einstein's audacious theory that light is a particle are his most famous works as a physicist and Nobel winner. The most well-known scientist of the 20th century is perhaps him.

In March 1879, he was born in Ulm, Württemberg. He had a great interest in nature and the capacity to comprehend challenging mathematical ideas even as a young man in Munich. He had an unremarkable high school experience, doing exceptionally well in arithmetic but completely failing the classics, which were then thought to be crucial for anybody planning to attend college. He detested school's dreary regimentation and uncreative atmosphere.

The second study established a lot of information regarding the nature of molecules and explained Brownian motion, which is the random jostling of molecules floating in a fluid. 16 years later, this study helped him win the physics Nobel Prize.

However, his third work, "On the Electrodynamics of Moving Bodies," was left out of the award's wording. The third article was the one that would have the biggest impact on contemporary physics. It included Einstein's Special Theory of Relativity, which greatly simplified how we think about how radiation, like light, interacts with matter. Speaking about one body moving and another being motionless has no real significance, according to Einstein. Only in connection to one other can bodies be conceived of as moving;

This specifically implies that, regardless of the frame of reference, electromagnetic radiation's (such as light's) speed remains constant. Even well-known scientists struggled to comprehend this theory because of Einstein's insightful and audacious viewpoint. But over time, when the predictions made by his theory were repeatedly verified, the Special Theory of Relativity finally transformed how scientists thought about matter, space, time, and everything that interacts with them.

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The approximate heat transfer through 1.65 cm of air with a temperature difference of 23.0 °C is approximately 24.4 J/s.

To approximate the heat transfer through the air layer in the double-paned window, we can assume that the glass layers have a negligible impact on the heat flow. The heat transfer can be calculated using Fourier's Law of Heat Conduction, which states that the heat flow (Q) is proportional to the temperature difference (ΔT) and inversely proportional to the thickness (L) and thermal conductivity (k) of the material.

First, we need to calculate the effective thermal conductivity of the air layer due to its thickness and the thermal conductivity ratio between air and glass. Let's denote the thermal conductivity of air as k_air and the thermal conductivity of glass as k_glass. Since glass has a thermal conductivity roughly 36 times greater than air, we have k_glass = 36 * k_air.

Next, we calculate the effective thermal conductivity of the air layer as:

k_eff = (k_air * L_air) / (L_air + k_glass)

Substituting the given values, we have:

k_eff = (k_air * 0.0165 m) / (0.0165 m + 0.005 m) = 0.01309 * k_air

Now, we can calculate the heat flow per second through the air layer using the formula:

Q = (k_eff * A * ΔT) / L_air

Substituting the given values, we get:

Q = (0.01309 * k_air * 0.760 m^2 * 23.0 K) / 0.0165 m = 24.4 J/s

Therefore, the approximate heat transfer through 1.65 cm of air with a temperature difference of 23.0 °C is approximately 24.4 J/s.

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Answer:

I ATE APPLE PIE YESTERDAY

Explanation:

Answer:

 v = 220 m / s

Explanation:

This is a kinematics exercise, the expression for velocity is

          v = 25 t² - 80 t - 200

asks the velocity for time t = 6 s.

let's calculate

        v = 25 6² - 80 6 - 200

        v = 220 m / s

The velocity for the first six seconds when acceleration is zero is -44 m/s.

The velocity of an object is the rate of change displacement with time.

The velocity of the object for the first six seconds when the acceleration is zero is calculated as follows;

\(a = \frac{dv}{dt} \\\\a = 50t - 80\\\\0 = 50t - 80\\\\50t = 80\\\\t = 1.6 \ s\)

Velocity when time = 1.6 s

\(v(1.6) = 25(1.6)^2 - 80(1.6) - 200\\\\v(1.6) = -264 \ m/s\)

The velocity for the first six seconds when acceleration is zero.

\(v = v_{a =0} + v_6\\\\v = - 264 \ + 25(6)^2 - 80(6) - 200\\\\v = -44 \ m/s\)

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Answer:

20

Explanation:

because it wlll go slow

During ice skating, there are several energy transformations that occur within the system, involving the chemical energy stored in the body and its conversion into other forms of energy.

The skater's body possesses chemical energy stored in the form of carbohydrates and fats obtained from food. This chemical energy is converted into mechanical energy as the skater's muscles contract and generate force to propel themselves forward on the ice. The chemical bonds in the molecules of carbohydrates and fats are broken, releasing energy that powers muscular movement.

As the skater glides on the ice, friction comes into play. The mechanical energy of the skater is transformed into thermal energy due to the interaction between the skate blades and the ice surface. Some of the mechanical energy is dissipated as heat due to friction, causing the ice to melt slightly beneath the blades.

This thermal energy contributes to the increase in the temperature of the ice and the surrounding environment. There may be sound energy produced as the skate blades interact with the ice. When the skater pushes off the ice or performs certain movements, vibrations are created, leading to the emission of sound waves.

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Answer:

The common speed is 1.95 m/s

Explanation:

Law Of Conservation Of Linear Momentum

It states that the total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and velocity v is  

P=mv.  

If we have a system of bodies, then the total momentum is the sum of all of them:

\(P=m_1v_1+m_2v_2+...+m_nv_n\)

If a collision occurs, the velocities change to v' and the final momentum is:

\(P'=m_1v'_1+m_2v'_2+...+m_nv'_n\)

In a system of two masses, the law of conservation of linear momentum

is written as:

\(m_1v_1+m_2v_2=m_1v'_1+m_2v'_2\)

If both masses stick together after the collision at a common speed v', then:

\(m_1v_1+m_2v_2=(m_1+m_2)v'\)

The common velocity after this situation is:

\(\displaystyle v'=\frac{m_1v_1+m_2v_2}{m_1+m_2}\)

The truck of m1=1200 N (weight) travels at v1=2 m/s and hits a stationary mass (v2=0) of m2=30 N (weight). After the bodies collide, they keep moving together. Before we can calculate the common speed, we need to calculate the masses of the bodies, since they are given as weights.

\(m_1=\frac{P_1}{g}=\frac{1200}{9.8}=122.45 Kg\)

\(m_2=\frac{P_2}{g}=\frac{30}{9.8}=3.06 Kg\)

Now calculate the common speed:

\(\displaystyle v'=\frac{122.45 * 2+3.06 * 0}{122.45+3.06}\)

\(\displaystyle v'=\frac{244.9}{125.51}=1.95\ m/s\)

The common speed is 1.95 m/s

The subject depicted in the attached image is Astronomy and Astrophysics.

Astronomy is the scientific study of celestial objects such as stars, planets, galaxies, and other phenomena that exist outside of Earth's atmosphere.

Astronomers use a variety of methods to observe and study these objects, including telescopes, spacecraft, and computer simulations.

Astronomy is a broad field that includes many different sub-disciplines, such as astrophysics, planetary science, and cosmology.

Astronomers study the physical properties and behavior of celestial objects, such as their composition, temperature, motion, and evolution.

They also seek to understand the structure and history of the universe as a whole.

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Answer:

Explanation:

1. First draw a free body diagram of the scenerio (a block sliding down a a slant surface).
2. Then we analyze the forces and write equations that satisfy Fnet = ma. This will give us the acceleration as the block slides down the surface.

3. Last, we can use the kinematic equation (vf^2 = vi^2 + 2as) and to solve the final speed of the block.

Answer:

0

Explanation:

Physically:

Beginning point means initial point so you're basically going into circles which means a displacement of zero.

Mathematically:

\(d = x _{f} - x _{i}\)

We know

\(x _{f} =x _{i}\)

So we get

\(d = x _{f} - x _{f}\)

\(d = 0\)

Answer:

you need to attach a picture so I can answer it

A beaver runs at a speed of 2.0 m/s with 45 J of kinetic energy, then the mass is approximately 1.74 kg, and this can be calculated by using the  kinetic energy (KE) of an object that is KE = (1/2) ×m × \(v^2\).

KE = (1/2) ×m × \(v^2\).

where m= mass of the object, v=its velocity.

The beaver runs at a speed of 2.0 m/s with 45 J of kinetic energy. Substituting these values into the above equation

45 J = (1/2) ×m × \((2.0 m/s)^2\)

Simplifying this equation:

45 J = (1/2) × m × 4.0\(m^2/s^2\)

45 J = 2 m × 2 \(m^2/s^2\)

45 J = 4 \(m^3/s^2\)

\(m^3\) = 45 J / 4 \(s^2\)

\(m^3\) = 11.25 kg×\(m^2/s^2\)

Taking the cube root of both sides to solve for mass,

m = (11.25 kg×\(m^2/s^2)^(^1^/^3^)\)

m = 1.74 kg (rounded to two decimal places)

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Answer:

m=146.277kg which is rounded to 146kg

Explanation:

Remember that F=ma

But F represents not 250N, but 250cos(35)N since the force is being pulled above the horizontal.

So 250cos(35)=204.7880111 approximately, and since a=1.4m/s^2, we have 204.7880111=m(1.4m/s^2). Then we divide both sides by the acceleration to get the mass. So m=146.2771508kg which the nearest number is 146kg

Mass is always in kg, unless stated otherwise.

Answer:

146kg

Explanation:

right on edge

According to the given statement  5.50 *  10¹⁴Hz is the frequency of the incident light.

The photoelectric effect, which happens when light strikes a metal, can release electrons out of its surface. As the electrons that are expelled first from metal are known as emitted electrons, this process is also sometimes referred to as photoemission.

The following equation may be used to determine a photon's energy in terms of frequency:

E = hf

The work function must first be changed from electron volts (eV) to joules (J):

1 eV = 1.602 × 10⁻¹⁹ J

Hence, the work function is:

1.68 eV × 1.602 × 10⁻¹⁹ J/eV = 2.69 × 10⁻¹⁹ J

The emitted photon's kinetic energy is:

E = 9.60 × 10⁻²⁰ J

E = E0 + KE

where KE is the kinetic energy of the released electron and E0 is the work function.

Inputting the values, we obtain:

hf = E0 + KE

hf = 2.69 × 10⁻¹⁹ J + 9.60 × 10⁻²⁰J

hf = 3.65 × 10⁻¹⁹ J

When we solve for f, we obtain:

f = E/h = (3.65 × 10⁻¹⁹ J) / (6.626 × 10⁻³⁴ J s)

f = 5.50 × 10¹⁴ Hz

As a result, the incident light has a frequency of 5.50 *  10¹⁴Hz.

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Answer:

Deep ocean trenches, volcanoes, island arcs, submarine mountain ranges, and fault lines.

Explanation:

The horizontal velocity of the projectile as it leaves the launcher is 35 m/s.

The time of motion of the projectile is calculated by applying the following kinematic equation as shown below.

h = vt + ¹/₂gt²

where;

h = 0 + ¹/₂gt²

h = ¹/₂gt²

t = √(2h/g)

t = √(2 x 0.4 / 9.8)

t = 0.286 s

The horizontal velocity of the projectile as it leaves the launcher is calculated as follows;

v = x/t

where;

v = 10 m / 0.286 s

v = 35 m/s

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The net force on particle q₂, located between particles q₁ and q₃, is approximately 189000 N. The force exerted by particle q₁ on q₂ is positive and equals 252000 N, while the force exerted by particle q₃ on q₂ is negative and equals -63000 N.

To find the net force on particle q₂, we need to calculate the individual forces exerted on q₂ by particles q₁ and q₃ and then determine their sum.

The force between two charged particles can be calculated using Coulomb's law:

F = k * |q₁ * q₂| / r²

Where F is the force between the particles, k is the electrostatic constant (k ≈ 9.0 x \(10^9\) Nm²/C²), q₁ and q₂ are the charges of the particles, and r is the distance between them.

First, let's calculate the force exerted on q₂ by q₁:

F₁₂ = k * |q₁ * q₂| / r₁₂²

F₁₂ = (9.0 x \(10^9\) Nm²/C²) * |(8.0 μC) * (3.5 μC)| / (0.10 m)²

F₁₂ ≈ 252000 N

The force is positive because q₁ and q₂ have opposite charges.

Next, let's calculate the force exerted on q₂ by q₃:

F₂₃ = k * |q₂ * q₃| / r₂₃²

F₂₃ = (9.0 x \(10^9\)Nm²/C²) * |(3.5 μC) * (-2.5 μC)| / (0.15 m)²

F₂₃ ≈ -63000 N

The force is negative because q₂ and q₃ have the same charge.

Finally, we can find the net force on q₂ by summing the individual forces:

Net force = F₁₂ + F₂₃

Net force = 252000 N + (-63000 N)

Net force ≈ 189000 N

The net force on particle q₂ is approximately 189000 N.

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The magnitude of OC is approximately 5.8 units, and the angle between the x-axis and vector OC is approximately 59.0 degrees

To evaluate the magnitude of vector OC, which is represented by vector C = (-3, -5), we can use the formula for the magnitude of a vector. The magnitude of a vector (denoted as ||v||) can be calculated using the Pythagorean theorem.

Magnitude of OC = ||C|| = √((-3)^2 + (-5)^2) = √(9 + 25) = √34 ≈ 5.8

To find the angle between the x-axis and vector OC, we can use trigonometry. The angle can be determined by finding the arctan of the y-component divided by the x-component of vector C.

Angle = arctan(-5 / -3) = arctan(5/3) ≈ 59.0 degrees

Therefore, the magnitude of OC is approximately 5.8 units, and the angle between the x-axis and vector OC is approximately 59.0 degrees (rounded to the nearest tenth).

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Answer:

Option C and D only

Explanation:

Option A is incorrect  because refractive index of a material is the ratio of speed of light in vacuum to the speed of light in a any given medium

Option B is correct as the speed of light in vacuum is always greater than the speed of light in any given medium.

Option C is correct

Option D is incorrect

Option E is incorrect because the denser the medium the more is the refractive index. Water is denser than air, hence it should have more refractive index as compared to that of air.

Answer:

Hurricanes are dangerous because they often carry high winds, in which destroy our homes and other recreational buildings. They also cause flooding, which is a threat to crops, animals, and shelters.

Explanation:

If you enjoyed my answer I would very much appreciate a brainliest. Thank you, and have a great day.

~Kai~

The article "Sunrise, Sunset...or Not?" by ReadWorks has a more formal tone compared to "The Ever-Changing Sky" by Megan McGibney.

In "Sunrise, Sunset...or Not?" the author uses scientific and technical terms such as "counterclockwise," "Arctic Circle," and "phenomenon," and provides a detailed explanation of the scientific reasoning behind the rising and setting of the sun.

In contrast, "The Ever-Changing Sky" by Megan McGibney has a more casual tone, using more colloquial language such as "clear day," "bright and shiny," and "People have always looked up at the sky with wonder." The author also uses phrases like "guess how long" and "right!" which implies that the author is addressing a less formal audience and is being conversational.

In all, "Sunrise, Sunset...or Not?" has a more formal tone because of its use of technical language, explanation of scientific concepts, and a generally informative and explanatory writing style.

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Sunrise, Sunset...or Not?

by ReadWorks

The sun is a wonderful thing for Earth. It is a star that heats the planet and makes life on

Earth possible. In addition, its light shines onto the planet. It is Earth's ultimate source of

energy.

Summer days may be longer than winter days, but for most people, the sun seems to do the

same thing each day: it appears to come up in the east for the day, and it appears to go down

in the west for the night. The sun looks like it rises in the east and sets in the west because of

how the earth spins in space. It spins toward the east, or counterclockwise. This means that

when most people look at the sky in the morning, the sun will first appear in the east.

The earth takes 24 hours to complete one turn. For most places on Earth, there is a daytime

and nighttime every 24 hours. But in some places for many days at a time, the sun might stay

up in the sky, or it might not even come up above the horizon.

In some parts of the world, the sun can be up in the sky for months. During part of the spring

and summer in Earth's Northern Hemisphere, the Northern Hemisphere is tilted towards the

sun so much that the sun in northern Alaska, which is located in the Arctic Circle, never goes

below the horizon. The Arctic Circle is an area at the top of the earth. In Barrow, Alaska, the

sun doesn't set for almost three months! This phenomenon is called the midnight sun, when

the sun has not set at midnight. Try sleeping through that!

During parts of the fall and winter in Earth's Northern Hemisphere, the Northern Hemisphere

is tilted in such a way that the sun doesn't come over the horizon in northern Alaska for a little

over two months. Therefore, nights last more than 24 hours. This phenomenon is called the

polar night. Although the sun never rises above the horizon during parts of the fall and winter

in the Arctic Circle, enough light often shines so that people who live there don't need

The Ever-Changing Sky

The Ever-Changing Sky

by Megan McGibney

Look up at the sky on a clear day. You will see the sun. It is bright and shiny, warming much of

what its light touches. Look up at the sky again at night. You may see the stars. They are also

bright and shiny, glimmering in the dark sky. You may also see the moon. It looks bright and

shiny, reflecting light from the sun. People have always looked up at the sky with wonder.

Some have even studied the sun, moon, and stars. These people, called astronomers, have

learned that those objects in the sky do not stay in the same place all the time.

The Ever-Changing Sky

extra quarter of a day.

Let's take a closer look at the moon. The earth does not revolve around the moon. Instead,

the moon revolves around the earth. It takes the moon about four weeks to complete a

revolution around the earth. The portion of the moon we, here on Earth, see changes over

this period of about four weeks as the moon's position around the earth changes. The

moonlight we see at night is the moon's reflection of sunlight onto Earth. The different ways

the moon appears to us are known as the moon's phases. The moon's phases depend on the

moon's position in relation to the earth and the sun.

The four-week period starts and ends with the new moon. The new moon cannot be seen

because the side of the moon lit by the sun is facing away from the earth.

Use the articles "The Ever-Changing Sky" and "Sunrise, Sunset...or Not?" to answer

questions 6.

6. Which article has a more formal tone? Support your answer with details from both texts.

Answers will vary.