The graph that BEST represents the speed of sound relative to the density of the medium it is traveling through is
A)
B)
C)
D)
Answers
Answer:if you're doing usatestprep the answer is B
Explanation:
The graph that BEST represents the speed of sound relative to the density of the medium it is travelling through is B.
What is speed of sound?Particle-to-particle interaction causes a pressure disturbance to propagate across a medium as a sound wave. In order to move energy through the medium, each disturbed particle exerts a force on the next neighbouring particle behind it. This causes that particle to become disturbed from rest.
A sound wave's speed is determined by how quickly the disturbance is transferred from particle to particle, much like any other wave. Speed is the amount of movement a disturbance makes per unit of time, whereas frequency is the number of vibrations a single particle makes per unit of time.
In the given four graph speed of sound versus density, in graph B there is linear variation. So graph B is best.
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Related Questions
a refrigerator has a power of 90w and is left on for 24 hours. A hair dryer has a power 900w and is on for 20 minutes. which statement correctly compares the energy used by these devices?
Answers
The refrigerator uses 7,776,000 J of energy, while the hair dryer uses 1,080,000 J. The correct comparison is C. the refrigerator uses 6,696,000 J more energy than the hair dryer.
To compare the energy used by the refrigerator and the hair dryer, we need to calculate the energy consumption for each device in joules (J).
Step-by-Step Calculation:
Refrigerator:Power = 90 W
Time = 24 hours = 24 × 60 × 60 seconds = 86,400 seconds
Energy used = Power × Time = 90 W × 86,400 s = 7,776,000 J
Hair Dryer:Power = 900 W
Time = 20 minutes = 20 × 60 seconds = 1,200 seconds
Energy used = Power × Time = 900 W × 1,200 s = 1,080,000 J
Now, we compare the two energies:
Energy used by the refrigerator = 7,776,000 J
Energy used by the hair dryer = 1,080,000 J
Difference in Energy Usage:
Difference = 7,776,000 J - 1,080,000 J
Difference = 6,696,000 J
Therefore, the correct statement is:
C. The refrigerator uses 6,696,000 J more than the hair dryer.
complete question:
a refrigerator has a power of 90w and is left on for 24 hours. A hair dryer has a power 900w and is on for 20 minutes. which statement correctly compares the energy used by these devices?
A. The refrigerator uses 1,080,000 J less than the hair dryer.
B. The refrigerator uses 3,224,000 J less than the hair dryer.
C. The refrigerator uses 6,696,000 J more than the hair dryer.
D. The refrigerator uses 7,776,000 J more than the hair dryer.
The air in tires can support a car because gases __________.
Answers
In fact, the force applied by the tires upwards to counter-balance the weight of the car (pushing downwards) is
[tex]F=pA[/tex]
where p is the pressure of the air inside the tires and A is the area of contact between the tire and the car. Therefore, a higher pressure means a larger force F, and eventually if the pressure p is higher enough the force F will be large enough to counterbalance the weight of the car.
Why is it important for scientists to replicate each other’s experiments?
Answers
Answer:
A. To determine if the scientific results are repeatable
Explanation:
You use a pulley to lift your bike to the ceiling for winter storage. when you bought the pulley, the salesman claimed that the pulley has a mechanical advantage of 10. while lifting the bike, you notice that the pulley is squeaking because it has rusted over the summer. you determine that the pulley now has an actual mechanical advantage of 3. what is its efficiency?
Answers
IMA- ideal / theoretical machine advantage
Efficiency = AMA / IMA
=3 / 10
=0.3
3
(actually over the theoretical
How much time does it take a power drill accelerating at 64.3 rad/s2 to achieve 1500. rotations per minute(RPM)?
Answers
[tex]1 rev = 2\pi rad[/tex]
[tex]1 min = 60 s[/tex]
We have
[tex]\omega _f = 1500 \frac{rev}{min} \cdot \frac{2 \pi rad/rev}{60 s/m}=0.157 rad/s [/tex]
the angular acceleration is given by
[tex]\alpha = \frac{\omega _f - \omega _i}{\Delta t} [/tex]
where [tex]\omega _i[/tex] is the initial velocity (in this case, zero), and [tex]\Delta t[/tex] is the time needed to accelerate the drill to its final velocity. Using [tex]\alpha = 64.3 rad/s^2[/tex], we can calculate [tex]\Delta t[/tex]:
[tex]\Delta t = \frac{\omega _f}{\alpha}= \frac{0.157 rad/s}{64.3 rad/s^2}=2.44 s [/tex]
Which of the following are heterogeneous mixtures (not homogeneous mixtures)?
Check all that apply.
A. Blood
B. A smoothie
C. Milk that is sold at the store
D. A cake mix
Answers
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A blender takes in 180 J of electrical energy. Of the 180 J, 90 J are transformed into kinetic energy, 60 J are transformed into thermal energy, and the rest is transformed into sound.
Answers
Based on the work done by the blender, the efficiency of the blender is 50%.
What is efficiency of a machine?The efficiency of a machine is a measure of the amount of useful work done by the machine compared to the work input into the machine.
Efficiency = work output/work input × 100%The useful work on a blender is the motion of the blender which is a form of kinetic energy.
The efficiency of the blender so then be:
work input = 180 J
work output = 90J
Efficiency = 90/180 × 00% = 50 %
Therefore, the efficiency of the blender is 50%.
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how high a hill would a 75 kg hiker has to climb to increase her gravitational potential energy by 10000 j
Answers
Answer:
[tex]13.60 \ m[/tex]
Explanation:
Given that,
Mass of the hiker is 75 kg
The gravitational potential energy by 10000 J
To solve :
The height of the hill.
Solve :
The gravitational potential energy of object , [tex]G=10000\ J[/tex].
Also, Mass of hiker, [tex]m=75 \ kg.[/tex]
Now,
The relation between Gravitational potential energy (G) and Mass of object (M) is given as:
[tex]G=m\times g \times h.[/tex]
Where , g is acceleration due to gravity, [tex]g=9.8\ m/s^2.[/tex].
Putting , values of G, g and m in above equation.
We get, [tex]10000=75\times 9.8 \times h\\\\h=\dfrac{10000}{75\times 9.8} \ m\\\\h=13.60\ m[/tex]
Hence , this is the required solution.
If a car increases its speed from 20 mph to 60 mph, by what factor does the kinetic energy of the car increase
Answers
If a car increases its speed from 20 mph to 60 mph, then the kinetic energy of the car increases by a factor of 9.
What is Kinetic energy?
Kinetic energy is the energy which is present in the object which is under motion. Kinetic energy is a vector quantity due to the presence of both the magnitude and direction. The SI unit of kinetic energy is Joule.
KE = 1/2 × m × v²
where, KE = Kinetic energy,
m = mass of the object,
v = velocity of the object
KE₁ = 1/2m(20)²
KE₂ = 1/2m(60)²
Therefore, the factor by which the kinetic energy of the car can be increased can be calculated by taking ratio of the kinetic energy:
KE₁/ KE₂ = 1/2m(20)² / 1/2m(60)²
KE₁/ KE₂ = 400/ 3600
KE₁/ KE₂ = 1/9
Therefore, the factor by which the kinetic energy of car has been increased by 9.
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When a current flows through an ionic liquid such as salty water, the moving charges are?
Answers
In salty water ions are produced by the salt
here salt is NaCl
so it will break in Na⁺ and Cl⁻
They carry the current
Na⁺ moves towards cathode and Cl⁻ moves towards anode
So current is carrying by ions which are Na⁺ and Cl⁻
metabolic processes depend on which factor listed below A.ice B.atospheric nitrogen C.fresh water D.phosphorus
Answers
Which of these is most likely a step in the formation of soil? a. erosion of soil b. crystallization of rocks c. animals digging rocks d. solidification of organic matter
Answers
Which of the following processes add methane (CH4) to the atmosphere?
A.Breakdown of plant and animal remains in the soil.
B. Leakage from natural gas pipelines.
C. Food digestion by land animals.
D.All of the above.
Answers
Answer: D.All of the above.
Methane is a colourless odourless gas that develops abundantly in nature.
A.Breakdown of plant and animal remains in the soil: The plant and animal remains contains large amount of organic matter, which is decomposed by soil bacteria. This process results in formation of methane gas. The process takes place in the absence of oxygen, hence, called as anaerobic decomposition. This gas gets liberated to the external environment.
B. Leakage from natural gas pipelines: The natural gas is obtained as a fossil fuel from deep layers of the earth. This gas is excavated in order to use it as fuel to run vehicles and for cooking food. The gas may liberate to the external environment by leakage.
C. Food digestion by land animals: The land animals such as cow and buffalo discharge dung, which is a rich source of methane. The methane gets liberated from the cow dung to the external environment.
Therefore, all processes are responsible for liberation of methane to the external environment.
All of the above the following processes add methane (CH₄) to the atmosphere.All the options are correct.Hence D is the correct option.
What is methane?Methane is a colorless, odorless gas that occurs naturally in large quantities.
A.Soil bacteria digest plant and animal remnants: Plant and animal remains include a huge quantity of organic materials, which soil bacteria degrade.
Methane gas is produced as a result of this process. Anaerobic decomposition is a type of breakdown that occurs in the absence of oxygen. This gas is then released into the atmosphere.
B. Natural gas pipeline leakage: Natural gas is a fossil fuel that is extracted from deep layers of the earth.
This gas is mined in order to use it as a source of energy for cars and cooking. Leakage might allow the gas to escape into the environment.
C. Food digestion in land animals: Land animals digest food in a variety of ways.
Hence option D is correct.
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which of the following best describes a capacitor
Answers
Answer:
Two parallel metal plates that can store charge
Explanation:
Which of the following can influence one???s ability to detect stimuli and increase one???s responsiveness to stimuli in dangerous situations?
A.
stimuli criteria
B.
response criteria
C.
difference threshold
D.
detection threshold
Answer: B response criteria
Answers
I hope this helps!!
The one that can influence ones ability to detect stimuli and increase responsiveness to stimuli in dangerous situations is response criteria. The correct option is B.
What is stimuli?Stimulus is defined as any event or change in the external environment that causes a specific functional response in an organ or tissue.
The stimulus can be both internal and external. External stimuli such as sound and touch are detected by sense organs such as the ear and sensory receptors such as those in the skin.
A stimulus is an energy change (e.g., light or sound) that is registered by the senses (e.g., vision, hearing, taste, etc.) and serves as the foundation for perception in perceptual psychology.
A stimulus serves as the foundation for behavior in behavioral psychology (classical and operant conditioning).
Response criteria are those that can influence one's ability to detect stimuli and increase responsiveness to stimuli in dangerous situations.
Thus, the correct option is B.
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What is the most power in watts the ear can receive before the listener feels pain?
Answers
Final answer:
The human ear starts to feel pain at sound intensities of 1 W/m². There is a broad range of sound intensities that can be heard without pain, but anything at or above the pain threshold may cause immediate hearing damage.
Explanation:
The amount of power in watts that the ear can receive before a listener feels pain is at an intensity of 1 W/m². The human ear is very sensitive and can detect sounds with a minimum threshold of 10−12 W/m² (0 dB). However, exposure to intensities at or above 1 W/m² can be painful. For example, sounds that are much higher in intensity than this level can be unbearable and potentially harmful, potentially leading to immediate damage. It is essential to protect one's hearing with measures such as using earplugs or ear muffs, especially when exposed to sounds of high decibel levels.
If planet i is 30.3 million miles farther from the sun than planet ii, then planet iii is 24.6 million miles farther from the sun than planet i. when the total of the distances for these three planets from the sun is 196.2 million miles, how far away from the sun is planet ii?
Answers
planet i and planet iii equaled 54.9 million miles, that subtracted from 196.2 equals 141.3
So your answer is 141.3 million miles
As surface area increases, weathering rate
Answers
hope this helps some .-.
Match the situation with the energy transformation ITEMBANK: Move to Top A boy shooting a rubber band across the classroom A child going down a slide on a playground Rubbing your hands together to warm them on a cold day Turning on a battery operated light Using a dc electric motor Using a gas power heater to warm a room Using a hand crank generator to produce electric current Using the light in your room that is plugged into the wall Chemical potential energy transformed into radiant energy Gravitational potential energy transformed into kinetic energy Elastic potential energy transformed into kinetic energy Chemical potential energy transformed into thermal energy Electrical energy transformed into radiant energy Kinetic energy being transformed into thermal energy Electrical energy transformed into kinetic energy
Answers
Elastic potential energy transformed into kinetic energy
The initial energy is the energy stored in the muscles of the boy's arm, which is elastic potential energy. This is converted into motion of the rubber, therefore kinetic energy
A child going down a slide on a playground --> Gravitational potential energy transformed into kinetic energy
On top of the slide, all the energy of the child is gravitational potential energy due to its height with respect to the ground (E=mgh). when it moves down the slide, this is converted into kinetic energy, because the child acquires a speed v (E=1/2 mv^2)
Rubbing your hands together to warm them on a cold day --> Kinetic energy being transformed into thermal energy
When rubbing hands, we are moving them (kinetic energy), and this energy raises the temperature of the hand's surface (thermal energy)
Turning on a battery operated light -->
Chemical potential energy transformed into radiant energy
A battery works by mean of chemical reactions (chemical potential energy), producing light (so, emitting energy by radiation, i.e. radiant energy)
Using a dc electric motor --> Electrical energy transformed into kinetic energy
A dc electric motor works using currents (so, electrical energy), and the energy produced can be used for example to accelerate a car (kinetic energy)
Using a gas power heater to warm a room --> Chemical potential energy transformed into thermal energy
A gas power heater burns gases (so, chemical reaction, i.e. chemical potential energy) to raise the temperature of the room (thermal energy)
Using a hand crank generator to produce electric current --> Kinetic energy transformed into electrical energy
In a hand-crank generator, the handle is being rotated (kinetic energy) in order to produce an electric current (electrical energy)
Using the light in your room that is plugged into the wall --> Electrical energy transformed into radiant energy
The lamp works by using electrical current flowing into a resistor (electrical energy) and it produces light, so it emits energy by electromagnetic radiation (radiant energy)
a rigid tank of air is cooled (temperature decreased) the volume has to remain constant because it is a rigid tank the air pressure in the rigid tank ___
A. Increases
B. Decreases
C. Stays the same
20 points please help right away
Answers
PV/T =k
where k is a constant
P-pressure, T- temperature and V -volume
the volume is constant at both situations as its a rigid tank as mentioned in the questions.
Therefore we consider Volume to be constant , then equation is
P/T = kV
kV = c (new constant)
P/T = c
P = cT
Therefore pressure is inversely proportional to temperature, whatever change in pressure would cause the same kind of change in temperature as well.
therefore when T decreases, P also decreases.
Answer is B
12) Photosynthesis is a chemical reaction where carbon dioxide and water react to form glucose (C6H12O6) and oxygen gas. Which represents the proper balanced equations for photosynthesis?
Answers
Answer : The balanced chemical reaction will be,
[tex]6CO_2+6H_2O\overset{sunlight}\rightarrow C_6H_{12}O_6+6O_2[/tex]
Explanation:
Photosynthesis : It is a type of chemical reaction that occurs in the green plants or living organism.
During the photosynthesis process, the carbon dioxide reacts with water in the presence of sunlight to produce glucose and oxygen as a product.
The balanced chemical reaction will be,
[tex]6CO_2+6H_2O\overset{sunlight}\rightarrow C_6H_{12}O_6+6O_2[/tex]
In the photosynthesis reaction, carbon dioxide and water molecule are the reactants and glucose and oxygen are the products.
Electromagnetic waves can carry more data at higher frequencies. Why would a scientist opt to transmit data at a lower frequency instead?
What are the limitations of sending information using electromagnetic waves?
What are the differences between analog and digital signals?
What are the advantages of using digital signals over analog signals?
Using reliable internet sources, identify three ways we use analog and digital signals in our everyday lives.
Answers
Transmitting data over low frequency electromagnetic waves can reach great distances before attenuation because are not easily interfered with by obstacles like high frequency waves are. This is because they can diffract over obstacles and pass around them with less shadowing.
A disadvantage of using electromagnetic waves to transmit data is interference. One cause of interference is the transmission ton over same frequency hence the necessity to regulate these waves through policies. Other causes of interference are due to weather or obstacles.
Analogue signal is the decoding of electromagnetic waves into electric pulses (of varying amplitudes) by a decoder and pass the electric circuit in the electronics. However, in digital signal, electromagnetic waves are converted to binary format (0s and 1s). Therefore, analogue signal is a continous signal while digital is discretely broken down into bits.
Digital signal have the advantage of analogue signal over the fact that they can carry loads of information. Analogue signal draws more power than digital signal hence the later is eco-friendly. Digital signals are less likely to be affected by noise unlike analogue signals.
One major application for analogue signals is their use is speakers and microphones. Nonetheless, contemporarily, there are emerging digital microphones and speakers. A popular example of application of digital signal is in the mobile communication industry. The shift from analogue to digital has been greatly revolutionalized communication.
Answer:
Part One
1. Electromagnetic waves can carry more data at higher frequencies. Why would a scientist opt to transmit data at a lower frequency instead?
Higher frequencies of electromagnetic waves travel shorter distances but have higher data capacity. Scientists keep in mind that higher frequencies limit the range for sending information.
2. What are the limitations of sending information using electromagnetic waves?
Electromagnetic waves are sent through air signals, air signals are not private, so anybody in range can pick up the signal.
3. What are the differences between analog and digital signals?
Analog signals use more power, whereas digital signals use less. Analog signal value type is positive as well as negative, whereas digital signal is positive.
4. What are the advantages of using digital signals over analog signals?
The advantages of digital signals are better accuracy, less interference, and greater capacity for sending information.
The advantages of analog signals are strength and frequency change, and it travel in a continuous wave.
5. Using reliable internet sources, identify three ways we use analog and digital signals in our everyday lives.
Some examples of how we use analog and digital signals in our daily life is through phones and televisions. Phones use digital signals; they process our speech digitally and remove any unwanted sounds or echoes. Televisions use digital signals of video and audio processing to present them in a better version.
Part Two
1. Describe how radio telescopes are used to explore space.
Radio telescopes are used to detect radio waves in space.
2. How are radio waves used on Earth?
Radio telescopes are like televisions, right? So, using this information we then know that radio telescopes (television antenna) will detect radio waves that connect to satellite communication and that’s how we have television channels.
3. Why do radio telescopes convert radio waves (analog signals) to electrical (digital) signals for analysis? (Hint: What did the article say about the advantages of digital signals?)
The advantages of digital signals are better accuracy, less interference, and greater capacity for sending information.
Explanation:
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if a toaster produces 8 ohms of resistance in a 120 v circuit, what is the amount of current in the circuit
Answers
i = v/r = 120/4 = 30 amps
Two billiard balls of equal mass undergo a perfectly elastic head-on collision. if the speed of ball 1 was initially 2.00 m/s, and that of ball 2 was 3.00 m/s in the opposite direction, what will be their speeds after the collision? ball 1
Answers
- Let's start with conservation of momentum:
[tex]p_i = p_f[/tex]
Let's take as positive direction the initial direction of ball 1. Let's label with m the mass of the balls (they have same mass), with [tex]v_1[/tex] the final speed of ball 1, with [tex]v_2[/tex] the final speed of ball 2. The initial velocity of ball 1 is 2 m/s, while the initial velocity of ball 2 is -3 m/s (with a negative sign, because it is going in the opposite direction of ball 1). The conservation of momentum becomes
[tex](2 m/s) m - (3m/s)m = mv_1 + mv_2[/tex]
From which we find
[tex]v_2 = -1 m/s -v_1[/tex]
- Let's now write conservation of kinetic energy:
[tex]K_i = K_f[/tex]
which becomes
[tex] \frac{1}{2} m (2m/s)^2 + \frac{1}{2}m(3m/s)^2 = \frac{1}{2}mv_1^2 + \frac{1}{2}mv_2^2 [/tex]
Substituting
[tex]v_2 = -1 m/s -v_1[/tex]
as we found in the conservation of momentum, and simplifying, we get
[tex]v_1^2 + v_1 - 6m/s = 0[/tex]
which has two solutions:
[tex]v_1 = -3 m/s, v_2 =2m/s[/tex] (1)
[tex]v_1=2 m/s, v_2 = -3 m/s[/tex] (2)
The second solution is meaningless: in fact, the balls have exactly same velocity and direction as before the collision. This would mean they didn't collide at all, so we can neglect solution 2. And so, the solution of the problem is (1).
The final velocity of the first ball is 3 m/s and the final velocity of the second ball is 2 m/s in opposite direction.
The given parameters;
mass of the billiard balls = minitial speed of the first ball, u₁ = 2 m/sinitial speed of the ball u₂ = 3 m/sApply the principle of conservation linear momentum;
[tex]m_1u_1 \ + \ m_2u_2 = m_1v_1 + m_2v_2\\\\2m - 3m = mv_1 + mv_2\\\\-m = m(v_1 + v_2)\\\\-1 = v_1 + v_2[/tex]
Apply one-dimensional velocity;
[tex]u_1 +v_1 = u_2 + v_2\\\\2 + v_1 = -3 + v_2\\\\5 + v_1 = v_2[/tex]
From the first equation, the values of the final velocity is calculated as follows;
[tex]-1 = v_1 + 5 + v_1\\\\-1 = 2v_1 + 5\\\\-6 = 2v_1\\\\v_1 = -3 \ m/s[/tex]
then, v₂ = 5 - 3 = 2 m/s
Thus, the final velocity of the first ball is 3 m/s and the final velocity of the second ball is 2 m/s in opposite direction.
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What can cause the sea level to fall? ocean basins getting smaller or water being removed from the hydrological cycle ocean basins getting larger or water being removed from the hydrological cycle ocean basins getting larger or water returning to the hydrological cycle ocean basins getting smaller or water returning to the hydrological cycle
Answers
a) ocean basins getting smaller or water being removed from the hydrological cycle.
When ocean basins get smaller, there is less water in the oceans, and so the sea level falls down. Similarly, if water is removed from the hydrological cycle, there is less water going back to the oceans via precipitations (or coming from the land), therefore the sea level decreases.
ocean basins getting smaller or water being removed from the hydrological cycle
Which are states of matter? Check all that apply.
energy
gas
liquid
ion
plasma
solid
Answers
Liquid, gas, solid and plasma are States of matter.
What is matter?Matter is anything that have mass and occupied space usually getting it's mass from energy.
There are states of matter and they are;
Solid
Liquid
Gas
Plasma
A state of matter can be termed a physical property if it dies not change the chemical composition of the substance and is reversible.
A state of matter can be called chemical property if the chemical composition is change and it is irreversible.
For example water exist in three state of matter.
It is solid if it is ice, it is liquid if it is water and it is gaseous if it is water vapor.
Therefore, Liquid, gas, solid and plasma are States of matter.
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A photosensitive surface is illuminated with both blue and violet light. the light that will cause more electrons to be ejected is the
Answers
In fact, in the photoelectric effect, the number of photoelectrons emitted does not depend on the frequency of the light, but only on its intensity. The frequency of the light affects only the kinetic energy of the photoelectrons, because each photon carries an energy of
[tex]E=hf[/tex]
where h is the Plank constant and f is the frequency of the wave, and then this energy is converted into kinetic energy of the photoelectron. But the number of photoelectrons emitted depends only on the number of incoming photons, so it depends only on the intensity of the light. Therefore, violet and blue light cause the emission of the same number of photoelectrons.
Which ions are most abundant in a base?
Answers
The hydroxide ions is the most abundant in a base. A base is regarded as a
substance which reacts with an acid to form a salt.
The base has a characteristic feature of having a pH between 7.1 to 14.0.
Strong bases have a pH of about 12-14 while weak bases have a pH of
between 7.1-9.
Bases have hydroxide ions which is responsible for the basic nature of the
substance while an acid has abundant hydrogen ions which is responsible
for its acidic nature.
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Jodie sets two objects on a flat surface. Object A has a mass of 50g, while object B has a mass of 250g. Jodie pushes both objects with the same force and watches them speed up. Which object will speed up more? A. They speed up the same amount. B. Object B speeds up more. C. Object A speeds up more. D. Neither object speeds up.
Answers
Object A speeds up more
Two important economic activities in Norden are _____.
Answers
The Answer is:
Agriculture and Fishing