Which statements are true of the electron cloud model? Check all that apply. It is also known as the planetary model. It is considered the modern atomic model. It describes the probable locations of the electrons. It describes the specific locations of the electrons.

Answers

Answer 1

Answer:

-It is considered the modern atomic model.

-It describes the probable locations of the electrons

Explanation:

edge 2020

Answer 2

The correct answer is:

It is considered the modern atomic model. It describes the probable locations of the electrons.

The electron cloud model is another name used to describe the modern wave mechanical model of the atom.

It is the atomic model introduced by Erwin Schrodinger in 1927 based on the principles of quantum mechanics. It was an advancement over the Bohr model of the atom.

In this model, the atomic orbital is described as a region in space where there is a high probability of finding an electron. Hence, the electron is not found in specific orbits according to the Bohr model, rather, we describe the probability of finding the electron. This is the contemporary approach to the study of atomic structure.

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Which Statements Are True Of The Electron Cloud Model? Check All That Apply. It Is Also Known As The

Related Questions

Calculate the percent composition of Carbon in the
compound shown below. Record your answer with two
decimal places.
C18H18010

Answers

Answer:54.82%

Explanation:

Percentage of carbon = mass of carbon in that compound/ mass of the compund *100

216/394*100 = 54.82%

. KMnO4 oxidizes ethyl benzene to benzoic acid. If this reaction generally results in a 40 % experimental yield, how many grams of ethyl benzene are required to obtain 244 g of benzoic acid

Answers

Answer:

530.835 g

Explanation:

First we convert 244 g of benzoic acid (C₇H₆O₂) to moles, using its molar mass:

244 g benzoic acid ÷ 122.12 g/mol = 2.00 moles benzoic acid

Theoretically, one mol of ethyl benzene would produce one mol of benzoic acid. But the experimental yield tells us that one mol of ethyl benzene will produce only 0.4 moles of benzoic acid.

With the above information in mind we convert 2.00 moles of benzoic acid into moles of ethyl benzene:

2.00 moles benzoic acid * [tex]\frac{1molEthylBenzene}{0.4molBenzoicAcid}[/tex] = 5.00 moles ethyl benzene

Finally we convert moles of ethyl benzene (C₈H₁₀) into grams, using its molar mass:

5.00 moles ethyl benzene * 106.167 g/mol = 530.835 g ethyl benzene

Calculate the amount of heat required to completely sublime 96.0 gg of solid dry ice (CO2)(CO2) at its sublimation temperature. The heat of sublimation for carbon dioxide is 32.3 kJ/molkJ/mol. Express your answer in kilojoules.

Answers

Answer:

The correct answer is 70.41 kJ ≅ 70.4 kJ

Explanation:

The heat required to sublimate the solid at its sublimation temperature is calculated by using the following formula:

heat = ΔHs x moles of substance

Where ΔHs is the heat of sublimation, which is known (32.3 kJ/mol).

So, we have to calculate the moles of substance. For this, we can divide the mass of substance by the molecular weight of substance (CO₂):

mass CO₂ = 96.0 g

molecular weight CO₂ = (12 g/mol x 1) + (16 g/mol x 2) = 44 g/mol

⇒ moles of CO₂ = mass CO₂/molecular weight CO₂ = (96.0 g)/(44 g/mol) = 2.18 moles

Finally, we use the first formula to calculate the heat:

heat = ΔHs x moles = 32.3 kJ/mol x 2.18 mol = 70.41 kJ ≅ 70.4 kJ

Sodium carbonate reacts with silver nitrate according to the following balanced equation: Na2CO3 (s) + 2 AgNO3 (aq) → Ag2CO3 (s) + 2 NaNO3 (9) If 3.60 g of Na2CO3 is allowed to react with 5.14 g of AgNO3, what mass of Na2CO3 will remain at the end of the reaction?
a) 2.01 g
b) 1.54 g
c) 0.423 g
d) 0.0150 g
e) 0g

Answers

Answer:

a) 2.01 g

Explanation:

Na₂CO₃ (s) + 2AgNO₃ (aq) → Ag₂CO₃ (s) + 2NaNO₃

First we convert 0.0302 mol AgNO₃ to Na₂CO₃ moles, in order to calculate how many Na₂CO₃ moles reacted:

0.0302 mol AgNO₃ * [tex]\frac{1molNa_2CO_3}{2molAgNO_3}[/tex]  = 0.0151 mol Na₂CO₃

So the remaining Na₂CO₃ moles are:

0.0340 - 0.0151 = 0.0189 moles Na₂CO₃

Finally we convert Na₂CO₃ moles into grams, using its molar mass:

0.0189 moles Na₂CO₃ * 106 g/mol = 2.003 g Na₂CO₃

The closest answer is option a).

which of the following is the best definition for volume
a. solids are the only matter with volume
b. all energy has volume
c. volume is the three-dimensional size of an object
d. gases do not have volume

Answers

Answer:

C

Explanation:

I hope that helps!!! it kinda gave you the answer though

I believe the answer is c

what is a biohazard?

Answers

Answer:

a risk to human health or the environment arising from biological work, especially with microorganisms.

Explanation:

A biological hazard, or biohazard, is a biological substance that poses a threat to the health of living organisms, primarily humans. This could include a sample of a microorganism, virus or toxin that can adversely affect human health. A biohazard could also be a substance harmful to other animals.

Help please! I’ll give brainliest!

Answers

32 h this is because this problem

hurry plaese big points brainliest

Answers

Answer:

No because a straw is plastic look at it by this was, the energy used to create one metal straw is roughly equivalent to creating 90 plastic straws, and also produces carbon emissions equivalent to 150 plastic straws. This may not seem like a lot, but in order to offset the environmental impact of creating a metal straw, it must be used over 150 times

Explanation:

What isotope has 12 protons, 13 neutrons and 12 electrons?

Answers

Answer: Magnesium

Magnesium, in its elemental form, has 12 protons and 12 electrons. The neutrons are a different matter. Magesium's average atomic mass is 24.305 atomic mass units, but no magnesium atom has exactly this mass.

Hope this helps....... Stay safe and have a Merry Christmas!!!!!!!! :D

When 80.0 mL of a 0.812 M barium chloride solution is combined with 40 mL of a 1.52 M potassium sulfate solution, 10.8 g of barium sulfate precipitates. What is the % yield of this reaction

Answers

Answer:

76.1%

Explanation:

The reaction that takes place is:

BaCl₂ + K₂SO₄ → BaSO₄ + 2KCl

First we determine how many moles of each reactant were added:

BaCl₂ ⇒ 80 mL * 0.812 M = 64.96 mmol BaCl₂ K₂SO₄ ⇒ 40 mL * 1.52 M = 60.8 mmol K₂SO₄

Thus K₂SO₄ is the limiting reactant.

Using the moles of the limiting reactant we calculate how many moles of BaSO₄ would have been produced if the % yield was 100%:

60.8 mmol K₂SO₄ * [tex]\frac{1mmolBaSO_4}{1mmolK_2SO_4}[/tex] = 60.8 mmol BaSO₄

Then we convert that theoretical amount into grams, using the molar mass of BaSO₄:

60.8 mmol BaSO₄ * 233.38 mg/mmol = 14189.504 mg BaSO₄14189.504 mg BaSO₄ / 1000 = 14.2 g BaSO₄

Finally we calculate the % yield:

% yield = 10.8 g / 14.2 g * 100 %% yield = 76.1%

according to the big bang theory, which describes the universe before the actual big bang occurred?

Answers

Answer:

the answer is hot,dense points; each smaller than an atom

Explanation:

the big bang theory was proposed to suggest the expansion of the universe by describing the origin of all components of the universe and its planetary bodies. its suggested that the whole universe was in a state of high temperature and highly dense points (which were smaller than atoms) but continuously expanded by cooling down which gave rise to the formation of subatomic particles, atoms, etc.

btw I found this on brainly

1. A football player throws a football 30 meters/second2 using 600 Newtons of force What
was the mass of the football?

Answers

Answer:

20 kg

Explanation:

The mass of the football can be found by using the formula

[tex]m = \frac{f}{a} \\ [/tex]

f is the force

a is the acceleration

From the question we have

[tex]m = \frac{600}{30} = \frac{60}{3} \\ [/tex]

We have the final answer as

20 kg

Hope this helps you

3. Gasoline, coal, batteries, and logs all have chemical energy. When they burn that chemical energy will be transformed into energy.​

Answers

Answer:

Thermal energy

Explanation:

When gasoline, coal, batteries and logs are all burn they transform chemical energy to thermal energy.

The chemical energy is the energy held between chemical chains and bonds within an atom.

When they combust, they release thermal energyChemical energy is a potential energy. The thermal energy is a kinetic energyIt increase the average motion of the particles in the mediumThe breaking bond when produces heat which is a form of thermal energy.

17. Which of the following represent the correct net ionic equations from the double replacement reaction of
calcium nitrate and potassium phosphate?
a. Caaq) + PO43- (aq) → CaPO4(s)
b. Q Ca2+ (aq) + 3 PO43- (aq) → Caz(PO4)3(S)
c. 3 Ca2+ (aq) + 2 PO.3(aq) → Caz(PO4)2(S)
d. 2 NO3(aq) + Ca2+
+ Ca(NO3)2(S)

Answers

Answer:

D. 2 NO3(aq)+Ca2+

Explanation:

Reaction of calcium nitrate and potassium phosphate produce calcium phosphate and potassium nitrate. The net ionic equation for this is written as : [tex]3 Ca^{2+} (aq) +2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s)[/tex]. Thus option C is correct.

What is double displacement reaction?

In a double displacement reaction, two species or groups in reactant side are displaced in the products.

In a balanced chemical equation, all the reactants have to be in proper stochiometric ratio and the states of all species are mentioned in brackets.

In an ionic equation all the ions and charges are balanced both side and the number of each elements on both side too. The net ionic equation represents the formation of a solid product from its ions.

The balanced molecular equation and complete ionic equation are written for the given  reaction below:

[tex]3 Ca (NO_{3})_{2} (aq)+ 2K_{3} PO_{4} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s) + 6 KNO_{3}(aq)[/tex]

[tex]3 Ca^{2+} (aq) +6 NO_{3}^{-} + (aq)+ 6K^{+} + (aq) 2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s) + 6 NO_{3}^{-} (aq)+ 6K^{+} (aq)[/tex]

Now when the same species on both side is cancelled, then the net ionic equation is written as:

[tex]3 Ca^{2+} (aq) +2PO_{4} ^{3-} (aq) \rightarrow Ca_{3}(PO_{4} )_{2} (s)[/tex]

Therefore, the correct et ionic equation is option c.

To learn more about ionic equations, refer the link below:

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PLEASE HELP
This picture represents a model of:



Question 5 options:

Oxygen


Calcium


Boron


Neon

Answers

Answer:

The picture represents oxygen.

Explanation:

There are two notable ways you can figure this out:

1) Since there are eight protons, you can automatically know that you are looking for an element with an atomic number of 8. This is because the atomic number is the number of protons in an atom.

2) You can also note the number of electrons on the outer shell. These are called valence electrons. You can then see that the element has 6 valence electrons. Beginning with Lithium on the periodic table and count by ones going from left to right in period 2 of the periodic table until you get to 6. What element is that? It is indeed oxygen.

Answer:

Oxygen

Explanation:

Neons contain 8 protons and 10 ELECTRONS

Boron contains 5 protons an 5 electrons

calcium contains 20 electrons an 0 protons

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Hsnsgehsndgd

Answers

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Which two factors often determine the type of rock that is formed by a process?
A.The type of material that is present at the beginning of the process
B.The amount of time the process of rock formation takes
C.The season in which the rock formation process ends
D.Whether the process takes place north or south of the equator

Answers

Answer:

A and B

Explanation:

Trust me I just did it on a p e x

Answer: he’s correct it’s d and b for me but it’s the same answers

Explanation:

The net ionic equation for the dissolution of zinc metal in aqueous hydrobromic acid is ________.

Answers

Answer:

[tex]Zn(s)+2H^+(aq)\rightarrow Zn^{2+}(aq)+H_2(g)[/tex]

Explanation:

Hello!

In this case, since writing the net ionic equation implies the complete molecular equation, we should start by:

[tex]Zn(s)+2HBr(aq)\rightarrow ZnBr_2(aq)+H_2(g)[/tex]

Next, we represent the ionization of the aqueous species:

[tex]Zn(s)+2H^+(aq)+2Br^-(aq)\rightarrow Zn^{2+}(aq)+2Br^-(aq)+H_2(g)[/tex]

Whereas the spectator ions, those at both reactants and products are cancelled out so the net ionic equation is obtained:

[tex]Zn(s)+2H^+(aq)\rightarrow Zn^{2+}(aq)+H_2(g)[/tex]

Best regards!

explain how to convert the moles to litters and litters to moles

Answers

Converting from volume (liters) to moles: Divide your initial volume by the molar volume constant, 22.4 L. Converting from moles to volume (liters): Multiply your mole value by the molar volume constant, 22.4L.

How do I cook eggs? Please tell me

Answers

You just throw them on the pan with the flame all the way up it will be done in a second !
First pre heat the pan put oil in the pan then crack the egg on the pan and if ur scrambling play around with it for about 1 and a half minutes

You are asked to write observations about a 100g sample of Nitrogen-16 before it decays , but you running late. In order to make observations, you require at least 5g of material Can make observations you are 57 seconds late to the lab?

Answers

Answer:

You can not make the observation in the lab

Explanation:

We must know the amount of Nitrogen-16 that remains after 57 seconds before we can make our conclusion.

Hence, from;

N/No = (1/2)^t/t1/2

Where;

N = amount of Nitrogen-16 present after 57 seconds

No = 100g of Nitrogen-16 originally present

t = 57 seconds

t1/2 = half life of Nitrogen-16 which is 7.13 seconds

Substituting values;

N/100 = (1/2)57/7.13

N/ 100 =(1/2)^8

N/100 = 1/256

256N = 100

N = 100/256

N = 0.39 g

You can not make the observation because you need at least 5g of Nitrogen-16 and only 0.39 g is left after 57 seconds.

The minimum amount of sample required has been 5 grams, while the remaining sample has been 0.39 grams. Thus, it has not been possible to make the observations.

The half life can be defined as the time required for the sample to reduce to half of its initial concentration. The half life can be given as:

Amount remained = Initial amount [tex]\rm \times\;\dfrac{1}{2}^\dfrac{time}{Half-life}[/tex]

The half life of nitrogen 16 has been 7.13 second.

The initial concentration of the sample has been 100 grams.

The concentration of sample remained after 57 seconds has been:

Amount remained = 100 [tex]\rm \times\;\dfrac{1}{2}^\dfrac{57\;sec}{7.13\;sec}[/tex]

Amount remained = 0.39 grams.

The amount of sample remained after 57 seconds has been 0.39 grams.

The amount of sample required for the analysis has been 5 grams, after 57 seconds only 0.39 grams of sample has been remaining. Thus, the student will not be able to made analysis of nitrogen-16.

For more information about the sample decay, refer to the link:

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Under conditions of constant temperature and amount of substance, a plot of pressure VS. volume for an ideal gas will result in:__________.
a) a line
b) a parabola
c) a logarithmic function
d) none of the above

Answers

Answer:

d) none of the above

Explanation:

The law that describes the relationship between pressure and volume of an ideal gas (under constant temperature and amount of substance) is Boyle's law.

It states that pressure is inversely proportional to the volume. This would mean that a graph of P vs 1/V would be a line.

See the attached picture for a graph of P vs V.

A plot of pressure VS. volume for an ideal gas will result in d) none of the above

The following things should be considered:

Boyle's law means the law that shows the relationship that lies between the pressure and volume of ideas gas that involved the same temperature and the substance amount.Also, the pressure should be inversly proportional with respect to the volume.

Therefore we can conclude that a plot of pressure VS. volume for an ideal gas will result in d) none of the above

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pls help I I alot of HELP​

Answers

Answer:

They need more oxhygen to fraction to incresse

Explanation:

Calculate the molarity of the two solutions.
The first solution contains 0.350 mol of NaOH in 1.05 L of solution.
molarity:

The second solution contains 14.3 g of NaCl in 879 mL of solution.
molarity:

Answers

1. 0.33 M

2. 0.278 M

Further explanation

Molarity is a way to express the concentration of the solution

Molarity shows the number of moles of solute in every 1 liter of solute or mmol in each ml of solution

[tex]\large{\boxed {\bold {M ~ = ~ \frac {n} {V}}}[/tex]

Where

M = Molarity

n = Number of moles of solute

V = Volume of solution

1. 0.350 mol of NaOH in 1.05 L of solution.

n=0.35

V=1.05 L

Molarity :

[tex]\tt M=\dfrac{0.35}{1.05}=0.33[/tex]

2. 14.3 g of NaCl in 879 mL of solution.

mol NaCl(MW=58.5 g/mol) :

[tex]\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{14.3~g}{58.5~g/mol}=0.244[/tex]

Molarity :

[tex]\tt M=\dfrac{0.244}{0.879~L}\\\\M=0.278[/tex]


If you heat a piece of copper, it combines with oxygen from the air to form a black layer of
copper oxide

A) Write a word equation for this reaction

B) How would the mass of your piece of copper change as you heated it?

C) Why would this happen?

Answers

Answer:

A. When a piece of copper is heated, it combines with oxygen to form copper oxide. The chemical reaction for the same is as follows:

              2 Cu (s) + O2(g) => 2CuO

B. The mass of the piece of copper will remain same and there will be no change in its mass. However, its volume will increase, so its density will decrease.

C. This is so because heating copper in its elemental form is a physical change and there is no change in mass during a physical change. Hence, the mass of copper remain same.

Which of these elements has the highest first ionization energy?
a) As
b) Ga
c) Bi
d) Cs
e) K

Answers

Answer:

Cesium (Cs)

Explanation:

This eliment has an ionization energy of 3,8939

What is the mass of H2SO4 in a 38.2-cm3 sample of concentrated sulfuric acid that has a density of 1.84 g/cm3 and consists of 98.3% H2SO4

Answers

Answer:

69.09 g

Explanation:

First we calculate the mass of the sample of concentrated H₂SO₄, using the given volume and density:

Mass = density * volumeMass = 1.84 g/cm³ * 38.2 cm³ = 70.288 g

There are 70.288 grams of solution, of which 98.3% is H₂SO₄. Thus the H₂SO₄ mass is:

70.288 g * 98.3/100 = 69.09 g

Taking into account the definition of density and percentage by mass, the mass of H₂SO₄ in a 38.2 cm³ sample of concentrated sulfuric acid is 69.09 grams.

Definition of density

But first you must know the definition of density. Density is defined as the property that matter, whether solid, liquid or gas, has to compress into a given space.

In other words, density is a quantity that allows us to measure the amount of mass in a certain volume of a substance. Then, the expression for the calculation of density is the quotient between the mass of a body and the volume it occupies:

[tex]density=\frac{mass}{volume}[/tex]

Mass of solution

In this case, you know that:

Density= 1.84 [tex]\frac{g}{cm^{3} }[/tex]

Volume= 38.2 cm³

Replacing in the definition of density:

[tex]1.84 \frac{g}{cm^{3} }=\frac{mass}{38.2 cm^{3} }[/tex]

Solving:

mass= 1.84 [tex]\frac{g}{cm^{3} }[/tex]×38.2 cm³

mass= 70.288 g

So, the mass of the solution is 70.288 grams.

Definition of percentage by mass

The percentage by mass expresses the concentration and indicates the amount of mass of solute present in 100 grams of solution.

In other words, the percentage by mass of a component of the solution is defined as the ratio of the mass of the solute to the mass of the solution, expressed as a percentage.

The percentage by mass is calculated as the mass of the solute divided by the mass of the solution, the result of which is multiplied by 100 to give a percentage. This is:

[tex]percentage by mass=\frac{mass of solute}{mass of solution}x100[/tex]

Mass of H₂SO₄

In this case, you know:

percentage by mass=98.3%

mass of solute= ?

mass of solution= 70.288 grams

Replacing in the definition of percentage by mass:

[tex]98.3=\frac{mass of solute}{70.288 grams}x100[/tex]

Solving:

[tex]\frac{98.3}{100} =\frac{mass of solute}{70.288 grams}[/tex]

[tex]0.983=\frac{mass of solute}{70.288 grams}[/tex]

0.983× 70.288 grams= mass of solute

69.09 grams= mass of solute

The mass of H₂SO₄ in a 38.2 cm³ sample of concentrated sulfuric acid is 69.09 grams.

Learn more about

density:

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percentage by mass:

brainly.com/question/18646836?referrer=searchResults

Please help me I need these answers

Answers

Answer:

Q8) True

Q9) First ionization energy

Q10) Metal oxides

Explanation:

A common property of group one elements (alkali metals) is their combination with water to form basic solutions. E.g 2K(s)+2H2O(l)→2KOH(aq)+H2​(g).

The distance of the outermost electron in the atom from the nucleus is inversely related to the first ionization energy. As the distance between the outermost electron and the nucleus in group 17 elements gets larger, the corresponding first ionization energies of elements in the group gets smaller.

Group 1 elements can combine with oxygen to give metal oxides. E.g  4K + O2 --> 2 K2O

How much heat is needed to increase the temperature of 15g of water from 10°C to 30°C? The specific heat of water is 4.18 (J/g °C).

Answers

Answer:

H=mc∆T

H=15×4.18×20

H=1254J


Which of thes statements about heating up land and water is true

Answers

Answer:

b its radiant energy that heats up the earth.

Explanation:

Answer:

The answer is D

Explanation:

Heat from the Earth's core and radiation from the Sun is transferred to the surface of the Earth by conduction. The warm land and water radiates infrared, some of which is absorbed by the atmosphere, adding to its thermal energy.

Other Questions
Which of these elements has the highest first ionization energy?a) Asb) Gac) Bid) Cse) K Select a logical argument about this poem. A. It can be inferred from this poem from Book of Songs that the narrator is pleased when the man is away from her. B. It can be inferred from this poem from Book of Songs that the narrator is saddest when the man is away from her. C. It can be inferred from this poem from Book of Songs that the narrator is happiest when the man is away from her. D. It can be inferred from this poem from Book of Songs that the narrator is content, when the man is away from her. Simplify the expression by combining like terms.15 + 12z 5z + 4y- 7 10x 2 6x = 3x 2 + x A. one solution B. no solutions C. infinitely many solutions Why is the Law of Conservation of Mass a law, rather than a theory?A. It has more scientific evidence supporting it B. It has both independent and dependent variablesC. It has been tested with the latest laboratory balances, which are very accurateD. It describes a repeatedly observed relationship, but it does not offer an exclamation what answer this is ? Mr. Gonzalez invested $4,200 into an account that earns a simple interest rate of 3% per year. What is the amount of interest Mr. Gonzalez will earn at the end of one year? PLSS I NEED HELPPPPPPP ASAP 30 points anyone have a amazon code that is still valid What song are you chest compressing to ?Staying aliveshotta stylethe fugeesOne What is the function of the structure identified by the red arrow? ClimatePolitical Units Vegetation Language What would be the best title for the list above? on khan my progress wont go up and i need 50% and i have 44 help please 6. Howmany totalmuscularexits arethere fromthe femalePelvis? Work out the 3rd term of the sequence 3n +5. a. 11b. 14c. 17 The Dust Bowl was a time In the 1930s when prairie states in the Midwest had farmlands torn apart by wind erosion and storms. This disaster caused food shortages and financial hardship. What practice is most helpful to prevent another similar tragedy? A. no-till farming to allow roots to hold soil together B. over watering of fields to keep soil wet C. terrace farming by putting walls up on hills D. agricultural reform to change the types of crops planted Which of the following is divisible by 3? how long did it take for a car to travel 20 meters with a speed of 10m/s Which of the following is NOT the responsibility of Congress?A. Servants of the people.B. Interest groups.C. Political parties.D. Vetoing Bills. PLEASE HELP URGENT! I'LL GIVE BRAINLIEST This graph represents the relationship between the growth of a plant and the amount of time that has passed since the plant was planted.Based on the data in the graph, which statement is true?The plant grows at a rate of 3 inches every 2 weeks.The plant grows at a rate of 6 inches every 2 weeks.The plant grows at a rate of 2 inches every 3 weeks.The plant grows at a rate of 4 inches every 6 weeks.