What does X represent in the following reaction?
239 239
93NP → 94Pu + X
A) a neutron
C) an alpha particle
B) a proton
D) a beta particle

Answers

Answer 1

Answer:

D. beta particle

Explanation:

Pu has 94 protons which is only one more than Np (93), that means beta decay. Atomic mass stays the same in beta decay. Beta is very small particle so atomic mass stays at 239.

Answer 2

The given reaction is an example of beta decay where the atomic number of the nuclei increases by one unit and mass number remains unchanged. Therefore, the particle X is a beta particle or an electron.

What is beta decay?

Heavy unstable isotopes of atoms undergoes nuclear decay by the emission of charged particles such as alpha or beta particle. In alpha decay, the helium nuclei is emitted and in beta decay, electrons are emitted.

In alpha decay, the mass number of the nuclei decreases by 4 units and atomic number by 2 units. In beta decay, the mass number does not change but the atomic number increases by one unit.

Neptunium undergoes beta decay and forms the plutonium nuclei. Thus X is a beta particle. The reaction is written as follows:

[tex]\rm _{93} ^{239}Np \rightarrow _{94}^{239}Pu + _{-1}^{0}e[/tex]

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Related Questions

How many grams of Br are in 445 g CaBr2 ?

Answers

Explanation:

The mass of bromine is 79.904, and since there are two of them in the Calcium Bromide molecule, we'll multiply it by 2 to get 159.808. Dividing that by the full mass of the molecule then multiply it by 100 will give you the answer.

What is the Equation of Reduction in Mg+F2 gives MgF2, I WILL MARK YOU AS BRAINLIST

Answers

Answer:

Mg+F2= Mgf2

Explanation:

F 2 is an oxidizing agent, Mg is a reducing agent. ; Pale-yellow to greenish gas with a pungent, irritating odor.

what are the benefits of chemistry to the economy​

Answers

Answer:

The role of Chemistry in the field of Economics is as a driving force in all industries, from basic materials for industrial machinery to industrial raw materials.

How are all planets in the solar system similar?

A. They have a gas atmosphere.
B. They have a water atmosphere.
C. They have a gas-surface composition.
D. They have a rock surface composition.
THIS IS FOR SCIENCE!!!!!!
PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Answers

Answer:

They have a rock surface composition.

Explanation:

I hope this will help you

The ion with a +3 charge 28 electrons and mass number of 71

Answers

Answer:

gallium

Explanation:

Ga +++ as it is the only ion with that features

What is the mass grams that are in 3.52 × 10²⁵ molecules of I₂

Answers

Answer:

As you know, one mole of any substance contains exactly

6.022

10

23

molecules of that substance - this is known as Avogadro's number.

Notice that you're dealing with more than

6.022

10

23

molecules of carbon dioxide, which means that you'll also be dealing with more than one mole of the compound.

More specifically, you'll have

1.5

10

26

molecules

1 mole CO

2

6.022

10

23

molecules

=

2.491

10

2

moles CO

2

Now, a substance's molar mass tells what the mass of one mole of that substance is. In carbon dioxide's case, its molar mass is equal to

44.01 g/mol

, which means that every mole of

CO

2

will have a mass of

44.01 g

.

In your case,

2.491

10

2

moles of

CO

2

would have a mass of

2.491

10

2

moles CO

2

44.01 g

1

mole CO

2

=

109.63 g

Rounded to two sig figs, the number of sig figs you have for the number of molecules of

CO

2

, the answer will be

m

C

O

2

=

110 g

Calculate the mass of naphthalene required to react stoichiometrically with the moles of 2-bromo-2-methylpropane that you have placed in the flask. Dispense that quantity of naphthalene into the weighing dish. There is some imprecision in delivering the powder onto the weigh boat, but a mass within 0.040 g of the calculated stoichiometric quantity will be sufficient for this experiment. Note that you can use a combination of the 1 g and the 0.1 g buttons to add the required mass. If you overshoot the goal, you can discard the weighing boat and get a new one. RECord the sample mass dispensed below. mass of naphthalene (g)

Answers

The reaction of 2-bromo-2-methylpropane and naphthalene is stoichiometrically  in a mole ratio of 1:1.

Notice that in the question, the moles of 2-bromo-2-methylpropane placed in the flask wasn't mentioned. if I assume that it was 1.24 moles then;

1 mole of naphthalene reacts with 1 mole of 2-bromo-2-methylpropane

x moles of naphthalene reacts with 1.24 mole of 2-bromo-2-methylpropane

x = 1 * 1.24/1

= 1.24 moles of naphthalene

Molar mass of naphthalene  = 128.2 g/mol

Mass of naphthalene  = 128.2 g/mol * 1.24 moles of naphthalene

Mass of naphthalene  =159 g

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the half-life of uranium-232 is 69 years. If the nuclear byproduct contains uranium-232, it is not considered safe for human contact until 99.2% of it has been decayed. How long will this take

Answers

After 69 years, 50% of the element has decayed
After 1 year, then,
x = 0.5/69 = 0.00724
0.724% of uranium-239 has been decayed.
To find how long it will take for 99.2% of the element to decay, we can use a similar method:
x years/0.992 = 69 years/0.5
x = 136.896 years
Therefore, it will take 136.896 years for 99.2% of the nuclear byproduct to have decayed.
Let me know if you have any questions

It will take approximately 480 years for 99.2% of uranium-232 to decay.

The formula of radioactive half-life = [tex]\frac{N}{N₀} = (\frac{1}{2})^{n}[/tex]

Where N = amount of isotope remaining

N₀ = original amount of isotope

n = number of half-lives

From the given values:

N = 100 5 - 99.2%

N = 0.8 % = 0.008

N₀ = 100% = 1

Substituting to find n

0.008/1 = (1/2)ⁿ

㏒₁₎₂0.008 = n

n = ㏒0.008/㏒(1/2)

n = 6.96

Therefore, number of half-lives n = 6.96

One half-life = 69 years

6.96 half-lives = 6.96 * 69 = 480.24 years

Therefore, it will take approximately 480 years for 99.2% of uranium-232 to decay.

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Gimme the sandmeyer's reaction!!!​

Answers

Explanation:

HERE IS YOUR ANSWER.....

At a constant temperature, a sample of gas occupies 1.5 L at a pressure of 2.8 ATM. What will be the pressure of this sample, in atmospheres, if the new volume is 0.92 L?

Answers

V1=1.5LV2=0.92LP1=2.8atmP2=?

Using boyles law

[tex]\boxed{\sf v\propto \dfrac{1}{p}}[/tex]

[tex]\\ \sf\longmapsto P_1V_1=P_2V_2[/tex]

[tex]\\ \sf\longmapsto P_2=\dfrac{P_1V_1}{V_2}[/tex]

[tex]\\ \sf\longmapsto P_2=\dfrac{2.8\times 1.5}{0.92}[/tex]

[tex]\\ \sf\longmapsto P_2=\dfrac{4.2}{0.92}[/tex]

[tex]\\ \sf\longmapsto P_2=4.56atm[/tex]

[tex]\\ \sf\longmapsto P_2\approx 4.6atm[/tex]

Answer:

[tex]\boxed {\boxed {\sf 4.6 \ atm}}[/tex]

Explanation:

We are asked to find the new pressure given a change in volume. We will use Boyle's Law, which states the volume of a gas is inversely proportional to the pressure. The formula for this law is:

[tex]P_1V_1= P_2V_2[/tex]

Initially, the gas occupies 1.5 liters at a pressure of 2.8 atmospheres.

[tex]1.5 \ L * 2.8 \ atm = P_2V_2[/tex]

The volume is changed to 0.92 liters, but the pressure is unknown.

[tex]1.5 \ L * 2.8 \ atm = P_2* 0.92 \ L[/tex]

We are solving for the final pressure, so we must isolate the variable P₂. It is being multiplied by 0.92 liters. The inverse operation of multiplication is division, so we divide both sides by 0.92 L.

[tex]\frac {1.5 \ L * 2.8 \ atm}{0.92 \ L} = \frac{P_2* 0.92 \ L}{0.92 \ L}[/tex]

[tex]\frac {1.5 \ L * 2.8 \ atm}{0.92 \ L}= P_2[/tex]

The units of liters cancel each other out.

[tex]\frac {1.5 * 2.8 \ atm}{0.92 }=P_2[/tex]

[tex]\frac {4.2}{0.92} \ atm= P_2[/tex]

[tex]4.565217391 \ atm = P_2[/tex]

The original measurements of pressure and volume have 2 significant figures, so our answer must have the same. For the number we calculated, that is the tenths place. The 6 in the hundredth place tells us to round the 5 up to a 6.

[tex]4.6 \ atm \approx P_2[/tex]

The pressure is approximately 4.6 atmospheres.

cuales son las caracteristicas de el livermorio

Answers

Answer:

Livermorium is a radioactive, artificially produced element about which little is known. It is expected to be a solid and classified as a metal. It is a member of the chalcogen group. Livermorium has four isotopes with known half-lives, all of which decay through alpha decay

Determine the number of hydrogen atoms connected to each carbon atom: The bond-line structure of a compound has a SMILES string of CC1CCN(CC1N(C)C2=NC=NC3=C2C=CN3)C(=O)CC#N. All the carbon atoms of the compound are highlighted and labeled a through p.

Answers

Answer:

dsgsdfd

Explanation:

A student records the time it takes for her pet rabbit to make it through a maze to a carrot. In one test, she has the
rabbit try to find the carrot at 8:00 AM after eating its first by meal of the day. In the other test, the rabbit tries to find the
carrot at 8:00 AM without having eaten its first meal of the day.
In this experiment, which variable is the outcome variable?
A. the time required to finish the maze
B. whether or not the rabbit finds the carrot
C. whether the rabbit is hungry or not
D. the time of day when the rabbit starts the maze mi

Answers

Answer:

The time required to finish the maze

The time required to finish the maze is the outcome variable of this experiment.

WHAT IS AN OUTCOME VARIABLE?

An outcome variable, also known as dependent variable or response variable, is the variable that the experimenter measures or records in the experiment.

The outcome variable responds to changes made to the independent variable, hence, the outcome variable is dependent on the independent variable.

In this question, a student conducts an experiment to determine the time it will take her pet rabbit to make it through a maze to a carrot.

She records the time it took the rabbit to finish the maze for each of the test. Hence, the outcome variable in this experiment is the time required for the rabbit to finish the maze.

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how many atoms of hydrogen and oxygen are present in 5 gm of HNO3









Answers

sjahbsbsbsbsbsjsjsnsnsnsnsnnsns

ANSWER: note the amounts of atoms of all the component in HNO3, which are 1 atom of hydrogen, 1 atom of nitrogen and 3 atom of oxygen.

What happens during the fourth stage of technological design that is not necessary during the sixth or seventh stages of scientific investigation?

A design is remodeled after analysis and tested again.
An initial design is implemented and analyzed to gather data.
Conclusions are made and communicated to others.
Criteria are stated to help judge the success of the process.

Answers

A. A design is remodeled after analysis and tested again.

Answer:

a design is remodeled after analysis and tested again

Explanation:


Compared to an atom of C-12, an atom of C-14 has
A) fewer protons
C) more neutrons
B) fewer neutrons
D) more protons

Answers

Explanation:

Carbon-12 atoms have stable nuclei because of the 1:1 ratio of protons and neutrons.

Carbon-14 atoms have nuclei which are unstable. C-14 atoms will undergo alpha decay and produce atoms of N-14. Carbon-14 dating can be used to determine the age of artifacts which are not more than 50,000 years old.

Draw Lewis structures to show how H+ is transferred when HNO₂ and NH₃ react with each other. The Lewis structure of HNO₂ is:

Answers

Attached are the Lewis structures:

Hope it helps...

[tex] \: \: \: [/tex]

PLEASE HELP!!
this is on USAtestprep
a)
b)
c)
d)

Answers

The answer would be A from what I know

Classify the following oxides as acidic, basic, amphoteric, or neutral:
(a) Select the acidic oxides:
A. CO₂
B. N₂O₅
C. Al₂O₃
D. NO
E. SO₃
(b) Select the basic oxides:
A. CaO
B. CO
C. SO₃
D. K₂O
E. BaO
(c ) Select the amphoteric oxides:
A. K₂O
B. Al₂O₃
C. CaO
D. CO₂
E. SnO₂
d) Select the neutral oxides:
A. CO
B. NO
C. SNO₂
D. N₂O₅
E. BaO

Answers

Answer:

(a).

» E. SO₃, sulphur trioxide.

(b).

» A. CaO, Calcium oxide.

» D. K₂O, potassium oxide.

» E. BaO, barium oxide.

(c).

» B. Al₂O₃, Aluminium oxide.

» E. SnO₂, tin (IV) oxide.

(d).

» A. CO, carbon monoxide.

» B. NO, nitrogen monoxide.

Explanation:

[tex]{ \underline{ \sf{ \blue{christ \:† \: alone }}}}[/tex]

a 82.6 L sample of gas exerts 350.8 mm hg pressure at 134.6 c°. what valine does the gas have at 736.4 mm hg and 42.8 c°
a. 30.5
b 4.13
c. 12.5
d. 134

need help ASAP

Answers

Answer:

nfururhrj waltz quiz amora7ersgdsYsdi6 whiz 53

96rduttie

In the following reaction, what element is gaining mass?

Mg(s) + CuSO4(aq) -> MgSO4(aq) + Cu(s)

A. Mg
B. None of these
C. Cu
D. O

Answers

Mg gained mass because it went from being a single element (on the reactant side) to being a molecule (on the product side).

Mg element is gaining mass. Hence, option A is correct.

What is a chemical equation?

A chemical reaction is a representation of symbols of the elements to indicate the number of substances and moles of reactant and product.

Mg gained mass because it went from being a single element (on the reactant side) to being a molecule (on the product side).

Hence, option A is correct.

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1. Consider the following thermochemical reaction for kerosene:
2 C12H26(l) + 37 O2(g)  24 CO2(g) + 26 H2O(l) + 15,026 kJ
(a) When 21.3 g of CO2 are made, how much heat is released?
(b) If 500.00 kJ of heat are released by the reaction, how grams of C12H26 must have been consumed ?
(c) If this reaction were being used to generate heat, how many grams of C12H26 would have to be reacted to generate
enough heat to raise the temperature of 750g of liquid water from 10oC to 90oC?
2. Consider the reaction: NaNO3(s) + H2SO4(l) → NaHSO4(s) + HNO3(g) ΔH° = 21.2 kJ
How much heat must absorbed by the reaction system to convert 100g of NaNO3 into NaHSO4(s)?
3. What is the enthalpy change when 49.4 mL of 0.430 M sulfuric acid reacts with 23.3 mL of 0.309 M potassium
hydroxide?
3.
H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(l) ΔH° = –111.6 kJ/mol

Answers

do you have the specific heat for part 2?

Entropy, the degree of disorder is related to the number of configurations that a system can adopt. If the entropy of a system is 71.85 J/mole*K, the number of configurations possible for this system is:

(a) 7188
​(b) 9967
​(c) 5665
​(d) 2183

Answers

I personally think it’s c I might be wrong tho

PLEASE HELP! A machine uses filtration to separate a component from orange juice. Which component does the machine most likely separate from the mixture?

A - Pigment
B - Sugar
C - Pulp
D - Water

Answers

Answer: c

Explanation:   Filtration is technically defined as the process of separating suspended solid matter from a liquid

Pulp is a lignocellulosic fibrous material prepared by chemically or mechanically separating cellulose fibers from wood, fiber crops .

Many commercial juices are filtered to remove fiber or pulp.

The correct answer is C, Pulp.

Orange is an example of a citrus fruit. Every citrus fruit has a pulp. The of pulp a citrus fruit is that stringy content in the endocarp of the fruit .

The pulp of a citrus fruit is where its juice is found.

When you want to prepare orange juice, you need to remove the pulp of the citrus fruit. This is done by filtering out the pulp from the juice.

Filtration is the process of removing larger particles. For a liquid juice, filtration is the process of removing solid particles from the orange juice.

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The reaction between NO2 and co to produce no and CO2 is thought to occur in two steps:

Step 1: NO2 + NO2 → + NO + NO3
Step 2: NO3 + CO → NO2 + CO2

The experimental rate law is rate = k[NO2]2.

Required:
a. Write the equation for the overall reaction. do not include phase abbreviations.
b. Identify the intermediate(s).

Answers

Answer:

Correct option is

A

Explanation:

The number of molecules of CO involves in the slowest step will be 0 because CO is not involve in the slowest step i.e. rate determing step.


If it takes 72 mL of 9 M KOH to neutralize 415 mL of sulfuric
acid (H2SO4) solution, what is the concentration of the H2SO4
solution?
M


Answers

The concentration of H₂SO₄ is 0.78 M

Explanation:

We'll begin by writing the balanced equation for the reaction. This is illustrated below:

H₂SO₄ + 2KOH —> K₂SO₄ + 2H₂O

From the balanced equation above,

Mole ratio of the acid, H₂SO₄ (nₐ) = 1

Mole ratio of the base, KOH (n₆) = 2

Finally, we shall determine the concentration of H₂SO₄. This can be obtained as follow:

Volume of base, KOH (V₆) = 72 mL

Concentration of base, KOH (C₆) = 9 M

Volume acid, H₂SO₄ (Vₐ) = 415 mL

Mole ratio of the acid, H₂SO₄ (nₐ) = 1

Mole ratio of the base, KOH (n₆) = 2

Concentration of acid, H₂SO₄ (Cₐ) =?

CₐVₐ / C₆V₆ = nₐ/n₆

Cₐ × 415 / 9 × 72 = 1/2

Cₐ × 415 / 648 = 1/2

Cross multiply

Cₐ × 415 × 2 = 648

Cₐ × 830 = 648

Divide both side by 830

Cₐ = 648 / 830

Cₐ = 0.78 M

Therefore, the concentration of H₂SO₄ is 0.78 M

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Which of the following has the greatest effect on colligative properties?

A. Calcium chloride (CaCl2)
B. Sodium chloride (NaCl)
C. Aluminum Nitrate (Al(NO3)3)
D. Epsom salt (MgSO4)

Answers

Answer:

C. Aluminum Nitrate (Al(NO3)3)

Explanation:

This is because, when Aluminium nitrate dissolves in water, it dissociates to form four ions ( one aluminium ion and three nitrate ions ). Since colligative property depends on number of particles or ions present ( roult's law ), this will create much effect.

[tex]Al(NO _{3} )_{3(aq)} → Al {}^{3 + } _{(aq)} + 3NO {}^{ - } _{(aq)}[/tex]

Answer:

aluminum nitrate (Al(NO3)3)

it has the greatest effect on collimation properties .

Explanation:

(c) is correct option

ANSWER THESE QUESTIONS PLEASE

No spam!! :/​

Answers

Answer:

By definition, a pure substance or a homogeneous mixture consists of a single phase. A heterogeneous mixture consists of two or more phases. When oil and water are combined, they do not mix evenly, but instead form two separate layers.

Explanation:

Sorry only knew the answer to the first question

Answer:

To make a saturated solution, 36 gm of sodium chloride is dissolved in 100 gm of water at 293 K. Find its concentration at this temperature.

Mass per cent is a way of expressing a concentration or describing the component in a particular mixture. The solution composition can be expressed in mass percentage that depicts the mass of solute present in a given mass of solution.

The quantity of solute is expressed in mass or by moles. For a solution, the mass per cent is described as the grams of solute per grams of solution, multiplied by 100 to get the percentage.

Concentration

Mass of sodium chloride (Solute) = 36gm

Mass of water (solvent) = 100 gm

Mass of solution = 36+100

∴ Mass of solution = 136 gm

Concentration = (Mass of Solute / Mass of Solution) * 100

Concentration = (36/136) × 100

Concentration = 26.47%

Temperature

If temperature increases, solubility increases and if temperature decreases, solubility decreases.

It is possible to distinguish the particles of solute from those of solvent in a suspension, since particle size is bigger in suspensions, hence it is easier to distinguish the particles of solute.

Explanation:

How many shapes contains the same text: KTKEIHLPEQMKJAPDEK

Answers

In this figure, four shapes contains the same text as in the red oval. The text given in the red oval is KTKEIHLPEQMKJAPDEK.

What is shape?

Shape is "the form of an object or its outline, outer boundary or outer surface".

What is text?

Text is "a collection of words or letters that are understandable by the reader".

What is an oval?

Oval is a rounded and slightly elongated outline or shape like that of an egg.

Hence, four shapes contains the same text as in the red oval.

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Could someone help me with this too? Much appreciated! I am a bit stuck.

Answers

Answer:

CO

Explanation:

Other Questions
Write any four reasons why Nepal's HDI in not up to the mark? Imagine that you are using a similar computer simulation to conduct an experiment on ph value of different liquid hand soap solutions and water. What is a potential source for error in such a computer model? Please help!! In what ways did the conservative revolution of the 1980s and 1990s fail in its promise of tax cuts equaling balanced budgets? (hint- national debt increased 220% from 1981-1992- who were the presidents?) Write x2 2x 3 = 0 in the form (x a)2 = b, where a and b are integers. (1 point) (x 4)2 = 3 (x 3)2 = 2 (x 2)2 = 1 (x 1)2 = 4 PLS HELP ME ON THIS QUESTION I WILL MARK YOU AS BRAINLIEST IF YOU KNOW THE ANSWER PLS GIVE ME A STEP BY STEP EXPLANATION!!In December, Doug's guitar store sold 10 acoustic guitars and 12 electric guitars. In January, they sold 13 acoustic guitars and 16 electric guitars. During which month did the guitar store sell a lower ratio of acoustic guitars to electric guitars?A. not enough informationB. JanuaryC. neither, the ratios are equivalentD. December Madeline is renting bowling shoes for $3.50 every time she goes bowling. She could get a good pair of bowling shoes for $68.If she goes once every two weeks during the year, would it be less expensive to rent or buy?A Buy B Rent El estado de California usa un sistema de trnsito.para rehabilitar a los infractores crnicos de leyes which decimal is equivalent to 188/11a.17.09b.17.009c.17.1709d.17.17090 when does the little black cat start purring ?why If a firm has constant returns to scale: multiple choice increasing output will not change average costs. the firm is not at the efficient scale. profits are maximized. increasing output will not change total costs. which of the following is called prime mebridian a)23 30` Nb)2330' Sc)8230'Ed)0' longitude Why is the Great Wall of China so famous in the world? gip mnh gii vi At the beginning of the year, Sigma Company's balance sheet reported Total Assets of $267,000 and Total Liabilities of $103,000. During the year, the company reported total revenues of $314,000 and expenses of $243,000. Also, owner withdrawals during the year totaled $64,000. Assuming no other changes to owner's capital, the balance in the owner's capital account at the end of the year would be: The countries that we are not invited to the treaty of versailles were You are a student in Danang city. You will describe your neighborhood for new students. You should say: 1/ Where to buy food 2/ Where to buy furniture 3/ Where to get a bus to university 4/ Where to send a package 5/ How do you feel about Danang city? Help me please.. 22. He gave her the book The fault in our stars as a birthday gift. A. She is given the book The fault in our stars as a birthday gift. B. The book The fault in our stars was given her as a birthday gift. C. The book The fault in our stars is given to her as a birthday gift. D. She was given the book The fault in our stars as a birthday gift. 23. Although I had all the necessary qualifications, they didnt offer me the job. A. Despite having all the necessary qualifications, they didnt offer me the job. B. In spite that I had all the necessary qualifications, they didnt offer me the job. C. In spite having all the necessary qualifications, they didnt offer me the job. D. Because of having all the necessary qualifications, they didnt offer me the job. 24. Shall we use Perfume Pagoda as a theme of the presentation? - She asked A. She asked why dont we use Perfume Pagoda as a theme of the presentation? B. She suggests using Perfume Pagoda as a theme of the presentation. C. She asked to use Perfume Pagoda as a theme of the presentation? D. She advised that we use Perfume Pagoda as a theme of the presentation?25. Go out of the class. His teacher told him A. His teacher told him to go out of the class. B. His teacher told him that he have to go out of the class. C. His teacher told him that he has to go out of the class. D. His teacher told him that he had go out of the class. The estimate obtained from a sample of which of the following sizes would most likely be closest to the actual parameter value of a population? Responsibility accounting holds managers responsible for ________. a. all costs charged to their subunit b. all costs charged to their subunit plus a share of company-wide fixed costs c. only the costs that they can control d. only the costs that they have personally approved