The length of the life cycle of a star depends on _.

distance from Earth
the nebula’s brightness
mass and the amount of matter
helium and the amount of matter

Answers

Answer 1

Answer:

c.mass and the amount of matter

Answer 2
C. Mass and the amount of matter

Related Questions

A rocket is fired vertically upwards with initial velocity 92 m/s at the ground level. Its engines then fire and it is accelerated at 4m/s2 until it reaches an altitude of 1200 m. At that point the engines fail and the rocket goes into free-fall. Disregard air resistance.

Answers

Answer:

The rocket above the ground is in 44 sec.

Explanation:

Given that,

Initial velocity = 92 m/s

Acceleration = 4 m/s²

Altitude = 1200 m

Suppose, How long was the rocket above the ground?

We need to calculate the time

Using equation of motion

[tex]s=ut-\dfrac{1}{2}at^2[/tex]

Put the value into the formula

[tex]1200=92t+\dfrac{1}{2}\times4t^2[/tex]

[tex]2t^2+92-1200=0[/tex]

[tex]t=10\ sec[/tex]

We need to calculate the velocity

Using equation of motion

[tex]v=u+at[/tex]

Put the value into the formula

[tex]v=92+4\times10[/tex]

[tex]v=132\ m/s[/tex]

When the rocket hits the ground,

Then, h'=0

We need to calculate the time

Using equation of motion

[tex]h'=h+ut-\dfrac{1}{2}at^2[/tex]

Put the value into the formula

[tex]0=1200+132t-\dfrac{1}{2}\times9.8t^2[/tex]

[tex]4.9t^2-132t-1200=0[/tex]

[tex]t=34\ sec[/tex]

When the rocket is in the air it is the sum of the time when it reaches 1000 m and the time when it hits the ground

So, the total time will be

[tex]t'=34+10[/tex]

[tex]t'=44\ sec[/tex]

Hence, The rocket above the ground is in 44 sec.

What are the SI units for distance and time?

Answers

Answer:

distance is meters, time is seconds

Answer:

distance is meters(m)

time is seconds (s)

Explanation:

Which sentence describes Newton's first law?
A. Forces always come in pairs that have the same magnitude.
B. The action force applied by one object to another is opposite in
direction to the reaction force.
C. It takes a larger net force to accelerate an object at a greater rate.
D. Unbalanced forces cause an object to move.
SM

Answers

[tex]\Large{\red{\bf{\blue{\dag} Answer:-}}}[/tex]

Newton's First Law of Motion :

An object stays in rest or in uniform motion unless and until compelled by an external unbalanced force . This is also known as " Law of Inertia " .

Here this statement is best represented by the statement : Unbalanced forces cause an object to move. [ option c ]

More to know :-

Newton's 3 laws of motion :-

Newton's First Law of Motion :-

It states that an object stays in rest or in uniform motion unless and until compelled by an external unbalanced force . This is also known as " Law of Inertia " .

Ex - (i) We tend to fall backwards while standing in the bus , when it starts suddenly.

(ii) We tend to fall forward while standing in the bus , when it stops suddenly.

Newton's Second Law of Motion :-

It states that the rate of change of momentum is directly proportional to the applied force in the direction of the force . That is ∆p [tex]\propto[/tex] Force .

Ex - (i) When we push car & a truck with same force the car will have Greater acceleration due to less mass . (Imaginary case ).

(ii) We feel easy to push a empty cart than a full cart .

Newton's Third Law of Motion :-

It states that every action has equal and opposite reaction .

Ex - (i) We are able to walk on ground due to Newton's third law of motion .

(ii) When we push wall it also applies equal and opposite force .

"Unbalanced forces cause an object to move " is the sentence that describes Newton's first law.

Describe Newton's first law.

   A body remains in the state of rest or uniform motion in a straight line unless and until an external force acts on it.

      The object is to be rest if the velocity and acceleration are zero.  When an object is in motion, velocity is not equal to zero (v ≠ 0) but acceleration (a = 0) is equal to zero. Therefore, the object will continue in motion with constant velocity in the same direction.

Example:

      If we jump from a bus while moving, our body will be like still moving in the same direction of the vehicle. When your feet hit the ground, the grounds act on your feet and stop moving. You will fall because the upper part of your body didn't stop and you will fall in the direction you were moving.

     If the object have the greater mass, then the object will have more inertia. Forces can change the object's motion.

Hence, Option D is the correct answer.

Learn more about Newton's first law,

https://brainly.com/question/974124

#SPJ5

Giving brainlist so plz help
What were John Locke's 3 big ideas

A. Natural rights, consent of the people, and moral obligation to rebel.

OR

B. Life, Liberty, and property

Answers

Answer:

Among these fundamental natural rights, Locke said, are "life, liberty, and property." Locke believed that the most basic human law of nature is the preservation of mankind. To serve that purpose, he reasoned, individuals have both a right and a duty to preserve their own lives.

Explanation:

From Google

Can I have brainliest

difference between gravity and gravitation​

Answers

Answer:

Gravitation is the attractive force existing between any two objects that have mass. The force of gravitation pulls objects together. Gravity is the gravitational force that occurs between the earth and other bodies. Gravity is the force acting to pull objects toward the earth.

What does gravity do to objects as they:

a) are thrown up:

b) fall toward earth:

Answers

Answer:

B

Explanation:

Gravity is when objects are pulled down to earth

Doe the baby diaper tabs go to the front or back. Huggies diaper.

Answers

Answer:

back lol

Explanation:

Pull the tabs and wrap around to stick to the front of the diaper:)

Answer:

Front of the diaper

You take the straps that are connected to the back of the diaper and pull the. forward to attach to the front.

hope this helps.

m1=200g m2=150g
find the acceleration
the track is horizontal and frictionless

Answers

Answer:

50 or 1.3333

Explanation: Explanation you cancel out the mass and the force to see what your acceleration would be or you could divide F by M

When the white ball strikes the other colored balls, what can you say about the total momentum of all of the balls combined?

Answers

Momentum is never created or destroyed. It is conserved.

The cue stick gave the cue ball all the momentum there is on the table.  There's nothing on the table that can pour in any more momentum.

After the strike, with 15 or 16 balls rolling every which way around the table, the total momentum of all of them combined will be the same as the cue ball's momentum right now, before the strike.

If a 3.1g ring is heated using 10.0 J, its temperature rises 19.7°C. Calculate
the specific heat capacity of the ring.

Answers

Answer:

Since 10 J / 4.19 J /cal = 2.39 cal     is the heat absorbed by the ring

Q = Cs * m * (T2 - T1)      heat absorbed by ring

Cs = 2.39 cal / (3.1 g * 19.7 deg C) = .039 cal / (gm deg C)

10 J / 4.19 J /cal = 2.39 cal     is the heat absorbed by the ring, Q = Cs * m * (T2 - T1)      heat absorbed by ring. Cs = 2.39 cal / (3.1 g * 19.7 deg C) = .039 cal / (gm deg C).

What is Specific heat capacity?

The amount of heat required to raise the temperature per unit mass is known as specific heat capacity. The heat in Joules required to increase the temperature of 1 gram of sample by 1 Kelvin or degree Celsius is typically stated.

Water is an excellent temperature regulator because it has a very high specific heat capacity.

The amount of heat in joules needed to raise 1 gram of a substance by 1 Kelvin is known as the specific heat capacity (symbol: c). It could also be written as J/kgK. Molar heat capacity, measured in J/mol K, and volumetric heat capacity, measured in J/m3 K, are comparable values.

Therefore, 10 J / 4.19 J /cal = 2.39 cal     is the heat absorbed by the ring, Q = Cs * m * (T2 - T1)      heat absorbed by ring. Cs = 2.39 cal / (3.1 g * 19.7 deg C) = .039 cal / (gm deg C).

To learn more about specific heat capacity, refer to the link:

https://brainly.com/question/29766819?

#SPJ6

Give reasons.
a. A stretched catapult has potential energy.
b A stone on ground has zero energy.
C. Rolling a drum is work against friction.
d. Lifting a stone is work against gravity.
e. Work and energy both have same unit.​

Answers

a. A stretched catapult can do work when released so it must have potential energy.

b. A stone on the ground will not move on its own ever again so it has zero energy.

c. In order to roll an object there must be a friction force between the object and the ground (otherwise it will slide)

d. To lift a stone you must overcome the weight which is the force due to gravity.

e. Work and energy are both measured in Joules.

A freshly prepared sample of radioactive isotope has an activity of 10 mCi. After 4 hours, its activity is 8 mCi. Find: (a) the decay constant  and half-life T1/2; (b) How many atoms of the isotope were contained in the freshly prepared sample? (c) What is the sample's activity 30 hours after it is prepared?

Answers

Answer:

(a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]

The half life is 11.3 hr.

(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]

(c). The sample's activity is 1.87 mCi.

Explanation:

Given that,

Activity [tex]R_{0}=10\ mCi[/tex]

Time [tex]t_{1}=4\ hours[/tex]

Activity R= 8 mCi

(a). We need to calculate the decay constant

Using formula of activity

[tex]R=R_{0}e^{-\lambda t}[/tex]

[tex]\lambda=\dfrac{1}{t}ln(\dfrac{R_{0}}{R})[/tex]

Put the value into the formula

[tex]\lambda=\dfrac{1}{4\times3600}ln(\dfrac{10}{8})[/tex]

[tex]\lambda=0.0000154\ s^{-1}[/tex]

[tex]\lambda=1.55\times10^{-5}\ s^{-1}[/tex]

We need to calculate the half life

Using formula of half life

[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{\lambda}[/tex]

Put the value into the formula

[tex]T_{\dfrac{1}{2}}=\dfrac{ln(2)}{1.55\times10^{-5}}[/tex]

[tex]T_{\dfrac{1}{2}}=44.719\times10^{3}\ s[/tex]

[tex]T_{\dfrac{1}{2}}=11.3\ hr[/tex]

(b). We need to calculate the value of N₀

Using formula of [tex]N_{0}[/tex]

[tex]N_{0}=\dfrac{3.70\times10^{6}}{\lambda}[/tex]

Put the value into the formula

[tex]N_{0}=\dfrac{3.70\times10^{6}}{1.55\times10^{-5}}[/tex]

[tex]N_{0}=2.38\times10^{11}\ nuclei[/tex]

(c). We need to calculate the sample's activity

Using formula of activity

[tex]R=R_{0}e^{-\lambda\times t}[/tex]

Put the value intyo the formula

[tex]R=10e^{-(1.55\times10^{-5}\times30\times3600)}[/tex]

[tex]R=1.87\ mCi[/tex]

Hence, (a). The decay constant is [tex]1.55\times10^{-5}\ s^{-1}[/tex]

The half life is 11.3 hr.

(b). The value of N₀ is [tex]2.38\times10^{11}\ nuclei[/tex]

(c). The sample's activity is 1.87 mCi.

BRAINLIEST & 20 POINTS ANSWER THE BOTTOM TWO QUESTIONS PLEASE HURRY!!!!

Answers

Answer:

For 9 is 2,4,1 and 3.For 10 b-c moves 15 from each other and e-f moves 15 also from each other.

5)
(64(6-2) =
A)
62
B)
8-9
C)
122

12-8

Answers

Answer:

B 8-9 because you had to subtract that number or simplify. then your answer is 8-9

PLEASE HELP THIS IS DUE IN 10 MINUTES- (15 points!)
1st question- what are the weather fronts(use the pic for help)
2nd question- who has better weather— high pressure systems or low pressure systems and how do you know?
(Please add explanation)<3

Answers

Answer: I would say that B would have better weather because those dots on the right are cold fronts and the smooth side without the dots is a warm front. I hope this helps :)

Explanation:

Suppose a scientist conducts a series of experiments and the results are so amazing she wants to share them with other experts in her field Why would it be risky for her to make the results public on her own website before publishing them to a scientific journal

Answers

Answer:

The results have not been through the rigorous process of peer review

Explanation:

When a scientist conducts a study and obtains results, those results ought to be submitted to a reputable journal where the results would go through the rigorous protocol of peer review.

During this process, the reliability of the data presented is ascertained before the results are published for other scientists to see.

If the results are hurriedly published on the internet, many researchers who come in contact with the work may be fed with inaccurate information.

You walk east for 30 m, then decide to walk north foranother 30 m. What is the angle of direction of your displacement?​

Answers

Answer:

Displacement is 42.426 m NE and the angle is opposite/adjacent or 30/30 which would equal 1 degree which doesn't seem right but hopefully its an answer.

Explanation:

Cacao beans arrive in a factory from the areas where they grew. At the factory, the best beans are sorted and put into bags. After quality-control workers check the bags, a large truck transports the cacao beans to a commercial chocolate-producing company. Which organelle plays a similar role inside a cell?
A. cytoplasm
B. Golgi body
C. mitochondrion
D. ribosome
E. vacuole

Answers

Answer:

B. Golgi body

Explanation:

The Golgi body is the region where proteins are modified, packaged, and transported to the appropriate location, usually outside of the cell.

The cytoplasm is the intracellular fluid/space, the mitochondrion produces energy, the ribosome produces proteins, and the vacuole is a storage organelle.    

The Answer is B , Because the golgi body stores stuff for later use.

hope this helps

what are three effects of using only non-renewable resources? please help

Answers

Non-renewable resources need to be burnt. This means we release heat into the air, we release carbon dioxide into the air which causes greenhouse effect, we also reduce fossil fuels which are needed for other purposes.


Find the 7th term of the geometric sequence
1/8, 1/2, 2, ...

Answers

Answer:

512

Explanation:

Given sequence:

        1/8, 1/2, 2, ...

Unknown:

The 7th term of the geometric sequence  = ?

Solution:

To solve this problem, we apply the formula below;

       Sₙ   = arⁿ⁻¹

a is the first term

r is the common ratio

n is the nth term

  r  = [tex]\frac{\frac{1}{2} }{\frac{1}{8} }[/tex]    = [tex]\frac{1}{2} x 8[/tex]   = 4

Input the parameters and solve;

      Sₙ  = [tex]\frac{1}{8}[/tex] x 4⁷⁻¹

     Sₙ   = [tex]\frac{1}{8}[/tex] x 4⁶  = 512

Janel did an experiment to see which spices can kill bacteria. She mixed a spice with bacteria food called agar. She poured the agar and spice mix into a petri dish(a plate used for growing bacteria) and added bacteria. She did the same for five different spices. This is an example of

Answers

Answer:

Antibacterial activity

Explanation:

The antibacterial property does not allow bacterias to live in an environment. Many spices have the ability to show antibacterial activity, few of these spices can be named as cinnamon, turmeric, or clove. Because they have antimicrobial or antibacterial characteristics that is why they are used for food preservation, disease prevention, and provide many health benefits. But, not every spice has antibacterial characteristics, that is why Janel experimented with five different spices to see which amongst them possess antibacterial characteristics.

Hence the correct answer is Antibacterial activity.

explain the relationship between physics and biology​

Answers

Answer:

Biology is the study of living organisms. Physics is the study of matter and the laws of nature to understand the behavior of matter and the universe.

The answer above is correct my dude

A force applied to a 0.25 Kg hockey puck gives the puck an acceleration of 16 m/s2. What acceleration would the same force give to a 0.50 Kg baseball?

Answers

Answer:

8 m/s².

Explanation:

We'll begin by calculating the force applied to 0.25 Kg hockey puck. This is illustrated below:

Mass (m) = 0.25 Kg

Acceleration (a) = 16 m/s²

Force (F) =.?

Force (F) = mass (m) × acceleration (a)

F = ma

F = 0.25 × 16

F = 4 N

Therefore, a force of4 N was applied to the 0.25 Kg hockey puck.

Finally, we shall determine the acceleration in which the 4 N force will give to the 0.50 Kg baseball. This can be obtained as follow:

Mass (m) = 0.50 Kg

Force (F) = 4 N

Acceleration (a) =?

F = ma

4 = 0.5 × a

Divide both side by 0.5

a = 4 / 0.5

a = 8 m/s²

Therefore, the same force (i.e 4 N) applied to the hockey puck will give the 0.5 kg baseball an acceleration of 8 m/s².

Classify each of the following chemical reactions. Upper S plus upper O Subscript 2 right arrow upper S upper O subscript 2. Upper C a upper C l subscript 2 plus 2 upper A g upper N upper O subscript 3 right arrow upper C a (upper n upper O subscript 3) subscript 2 plus 2 upper A g upper C l. Upper Z n plus upper C u upper S upper O subscript 4 right arrow upper C u plus upper Z n upper S upper O subscript 4. 2 upper N a subscript 2 upper O right arrow 4 upper N a plus upper O subscript 2.

Answers

Answer:

synthesis and combustion

double replacement

single replacement

decomposition only

in that exact order edge 2020

The presented reactions are:

S + O₂ ⇒ SO₂    Synthesis or combination

CaCl₂ + AgNO₃ = Ca(NO₃)₂ + 2 AgCl   Double displacement

Zn + CuSO₄ = Cu + ZnSO₄   Single displacement

2 Na₂O = 4 Na + O₂   Decomposition

Let's consider and classify the following reactions.

S + O₂ ⇒ SO₂

This is a synthesis or combination reaction. 2 compounds combine to form another.

CaCl₂ + AgNO₃ = Ca(NO₃)₂ + 2 AgCl

This is a double displacement reaction. Both compounds exchange their cations and anions.

Zn + CuSO₄ = Cu + ZnSO₄

This is a single displacement reaction. A metal displaces other metal from its salt.

2 Na₂O = 4 Na + O₂

This is a decomposition reaction. A compound decomposes into 2 other compounds.

The presented reactions are:

S + O₂ ⇒ SO₂    Synthesis or combination

CaCl₂ + AgNO₃ = Ca(NO₃)₂ + 2 AgCl   Double displacement

Zn + CuSO₄ = Cu + ZnSO₄   Single displacement

2 Na₂O = 4 Na + O₂   Decomposition

Learn more: https://brainly.com/question/21392527

Most _________ rely on sellers offering their goods or services in exchange for money from buyers

Answers

Answer:

Businesses

Explanation:

I think not sure tho

A chestnut-colored horse mates with a white-colored horse to produce a roan-colored offspring. What type of inheritance pattern does this genetic expression represent? A. Artificial selection B. Codominance C. Incomplete dominance D. Multiple alleles E. Polygenic inheritance

Answers

Answer:

The correct option is B.

Codorminance.

Explanation:

The type of inheritance pattern is codorminance because in codorminance the two alleles in the gene are expressed, no allele was able to masked the express on the other allele. The chestnut colored horse allele is expressed likewise the white

colored allele too is expressed none of the two alleles mask the Expression of the other, the two are expressed to give offsprings roan colored which is an indication of the two expression.

Answer:

Codominance

Explanation:

Which is the best estimate for the width of a typical adult hand?

Answers

Answer:

About 4-5in

Explanation:

What must be true for a hypothesis to become generally accepted by
scientists?
A. It must involve lots of complicated math.
B. It must have been tested by many scientists.
O O O O
C. It must be presented by a famous scientist.
D. It must be proven true by one experiment.

Answers

Answer:

B It must have been tested by many scientists.

Explanation:

trust me :)

For a hypothesis to become generally accepted by scientists, It must have been tested by many scientists. Hence option B is correct.

What is hypothesis ?

A hypothesis is a theory put up to explain a phenomena. A hypothesis must be testable according to the scientific method for it to be considered a scientific hypothesis. Scientific hypotheses are often based on prior findings that cannot be adequately explained by the current body of knowledge. Despite the fact that the terms "hypothesis" and "theory" are sometimes used interchangeably, they are not the same thing. A working hypothesis is an acknowledged theory that has been tentatively supported and is put up for further investigation.

In formal logic, the term "hypothesis" is used to refer to the antecedent of a statement, or in the proposition, in a different sense.

Hence option B is correct.

To know more about hypothesis :

https://brainly.com/question/29519577

#SPJ5.

The air in a scuba tank is under more than 200 times the normal air pressure. Why should a filled scuba tank never be left in a hot car for an extended period of time?

Answers

Answer:

Burst open

Explanation:

it could create an explosion cause after some time the air wont be good anymore and staying inside a hot car is like someone sitting an oven it would burst open and create an explosion depending on the size of it

What is the design process (Engineering Design Process) 5 sentences

Answers

The design process is a approach taken to tackle projects into manageable sections.
Other Questions
1. What groups listed below have true cell walls?A. algaeB. mycoplasmasC. Gram-positive bacteriaD. fungiE. protozoans A famous celebrity has an extreme security system for their estate. The security system includes sensors in the ground as well as on the sides of the buildings. A loud truck drives down the road entering the estate. There is a sensor in the ground and another on the side of the security guards shed. If both sensors are 100m from the truck, which sensor will pick up the noise of the truck first and why? A. Guard Shed - The sensor on the security guards shed will detect the sound first because the sound is traveling through the air and sound will travel fastest through a gas. B. Ground - The sensor in the ground will detect the sound first because the sound is traveling through the dirt and sound will travel fastest through a solid. C. Same time - Because the sound is traveling through both the ground and the air at the same time, it will reach both the shed and the ground sensor at the same time. D. Neither sensor - 100m is too far for the sound to travel. Neither sensor will pick up the sound of the truck until it is closer to them. what aspect should you consider before adding pictures to documents Which of the following is a goal of the FBLA-PBL?A. Requiring all members to maintain straight A'sB. Facilitating the transition from school to workC. Serving the needs of businesses above studentsD. Discouraging school loyalty and scholarship A programmer created a piece of software and wants to publish it using a Creative Commons license. Which of the following is a direct benefit of publishing the software with this type of license?AThe programmer can ensure that the algorithms used in the software are free from bias.BThe programmer can ensure that the source code for the software is backed up for archival purposes.CThe programmer can include code that was written by other people in the software without needing to obtain permission.DThe programmer can specify the ways that other people are legally allowed to use and distribute the software. Ill give 10 points and brainliest What occured during the battles of trenton and princeton? Given: Lines y and z are parallel, and ABC forms a triangle. Prove: m5 + m2 + m6 = 180 Lines y and z are parallel. Triangle A B C sits between the 2 lines with point A on line y and points C and B on line z. Angle C A B is 2. Its exterior angle to the left is 1 and its exterior angle to the right is 3. Angle A B C is 6 and its exterior angle to the right is 7. Angle B C A is 5 and its exterior angle to the left is 4. Statements Reasons 1. ABC is a triangle 1. given 2. y z 2. given 3. 1 5; 3 6 3. ? 4. m1 = m5; m3 = m6 4. def. 5. m1 + m2 + m3 = mLAM 5. addition postulate 6. m1 + m2 + m3 = 180 6. def. Straight angle 7. m5 + m2 + m6 = 180 7. substitution Which could be the missing reason in Step 3? alternate interior angles are congruent alternate exterior angles are congruent vertical angles are congruent corresponding angles are congruent 1 pound of a certain candy cost $8, how many pounds can be purchased for $12? True or false Even peaceful encounters with Spanish conquistadors often resulted in the death of American Indians Which is a grievance. Question 4 (1 point)Why does the author include the detailed information about Poe's final days?aTo argue that Poe regretted dedicating his life to writing.bTo explain the likely cause of Poe's mysterious death,cTo highlight the alcoholism Poe suffered from.dTo suggest that Poe was plagued with suffered great up until his death. in what ways does pollination in gymnosperms differ from pollination in angiosperms? 10a^2b^0 for a=3, b=8 (239820491+122389102938)+(32193846789231+2318947291392918)= helppppp Which agricultural society emerged between 4000 and 2400 B.C.?MesopotamiaEgyptGreeceIndiaJapanChina helpp meeee will award brainliest Please hlp im timed on this In the first week of July, a record 1020 people went to the local swimming pool. In the second week,100 fewer people went to the pool than in the first week. In the third week,130 more people went to the pool than in the second week. In the fourth week,132 fewer people went to the pool than in the third week. What is the percent decrease in the number of people who went to the pool over these four weeks? A student lives in an apartment complex next to a park and train tracks. The student observes that they can hear the train coming sooner and from farther away when they are in front of their apartment and can only barely hear the train when they are in the park despite both being the same distance from the railroad tracks. The student developed the model above. Using the model, identify two potential wave phenomena that occur and are the reason behind why the student can only hear the train in front of the apartment complex. A. The train can be heard more easily in front of the apartment complex because of reflection and interference. As the sound comes from the train, the sound waves reflect off of the complex and interfere with each other increasing the amplitude of the wave to make it easier to hear. B. The train can not be heard as easily in the park because of reflection and diffraction. The sound reflects off of the trees in the park and diffract between the trees, this causes the waves to bend too much to be heard. C. The train can be heard more easily in front of the apartment complex because of diffraction and refraction. The sound waves diffract between the other buildings aiming them towards the apartment complex and then the sound refracts through the apartment complex which makes it more difficult to hear in the park. D. The train can not be heard as easily in the park because of interference and reflection. The other buildings in front of the park cause interference of the sound waves from the train and the trees in the park cause reflection making it too hard to hear the train.