Is coal limited or unlimited give reasons

Answers

Answer 1

Answer:

Limited

Explanation:

Once it is used once, it is not reusable. Also, there's a possibility to use ALL the coal there is. That's why it's an unrenewable source, unlike the sun, wind, or water that never ends. Those are renewable

Answer 2

Answer:

Limited.

Explanation:

Coal comes from plants the died 100-400 million years ago and takes million years to form. Therefore, Coal is limited.


Related Questions

Another name for a statovolcano is a _____ volcano because it is made of alternating layers of thick, sticky lava and volcanic rock and ash. A. shield B. cinder C. composite D. pyroclastic

Answers

Answer:

Bcinder

Explanation:

Calculate the molar mass of CH4 gas at STP when 5.46Lof the gas weighs 4g??​

Answers

Answer:

About 16.42 grams

Explanation:

[tex]PV=nRT \\\\(1)(5.46L)=n(0.0821)(273) \\\\n\approx 0.2436 \\\\4g/0.2436\approx 16.42[/tex]

Hope this helps!

whats the chemical formula for dilute hydroxide acid​

Answers

the chemical formula is OH −

What does "A" represent in a the standard form of a double replacement reaction? a.) otion b.) cation

Answers

Answer: cation

Explanation:

"A" represent in a cation in the standard form of a double replacement reaction. Therefore, option B is correct.

What is cation ?

Positively charged ions are known as cations. Negatively charged ions are known as anions. Ions are positively or negatively charged atoms or molecules. A balanced atom will become a positively charged cation if one or more electrons are lost.

In an electrical field, these ions are known as "cations" because they are positively charged and migrate toward the negative electrode (cathode).

The double-replacement reaction generally take up the form of AB + CD → AD + CB where A and C are positively-charged cations and B and D are negatively-charged anions.

Thus, option B is correct.

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Explain Redox tiltration and examples of half - life reactions.​

Answers

Answer:

Explanation:

Half life reactions take place in electrochemistry where u have to find the emf generated from a cell

E.g Mg(s)/Mg(aq)//Ag(aq)/Ag(s)

Cu+2AgNO

3



→2Ag+Cu(NO

3



)

2



start text, C, u, end text, plus, 2, start text, A, g, N, O, end text, start subscript, 3, end subscript, right arrow, 2, start text, A, g, end text, plus, start text, C, u, left parenthesis, N, O, end text, start subscript, 3, end subscript, start text, right parenthesis, end text, start subscript, 2, end subscript

How many grams of \text{Ag}Agstart text, A, g, end text will be produced from 19.0 \text{ g}19.0 g19, point, 0, start text, space, g, end text of \text{Cu}Custart text, C, u, end text and 125 \text{ g}125 g125, start text, space, g, end text of \text{AgNO}_3AgNO

3



start text, A, g, N, O, end text, start subscript, 3, end subscript?

Answers

Answer:

Mass of Ag produced = 64.6 g

Note: the question is, how many grams of Ag is produced from 19.0 g of Cu and 125 g of AgNO3

Explanation:

Equation of the reaction:

Cu + 2AgNO3 ---> 2Ag + Cu(NO3)2

From the equation above, 1 mole of Cu reacts with 2 moles of AgNO3 to produce 2 moles of Ag and 1 mole of Cu(NO3)2.

Molar mass of the reactants and products are; Cu = 63.5 g/mol, Ag = 108 g/mol, AgNO3 = 170 g/mol, Cu(NO3)2 = 187.5 g/mol

To determine, the limiting reactant;

63.5 g of Cu reacts with 170 * 2 g of AgNO3,

19 g of Cu will react with (340 * 19)/63.5 g of AgNO3 =101.7 g of AgNO3.

Since there are 125 g of AgNO3 available for reaction, it is in excess and Cu is the limiting reactant.

63.5 g of Cu reacts to produce 108 * 2 g of Ag,

19 g of Cu will react to produce (216 * 19)/63.5 g of Ag = 64.6 g of Ag.

Therefore mass of Ag produced = 64.6g

Which element is needed for
a. Bone and teeth formation.
b. Treatment of water.

Answers

Bone and teeth formation
Treatment of water

Answer:

a.calcium

b.chlorine

Which symbol can be used to indicate the pressure at which a chemical reaction is carried out?
25°C
2 atm
Pt

Answers

Answer:

2atm symbol can be used to indicate the pressure at which a chemical reaction is carried out

if the balloon is 67,000 L at STP, what volume would it be if the air temperature cool to10.0°C in the pressure dropped to 99.2kPa as the balloon went higher?

Answers

Answer: The volume is 70872 L

Explanation:

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

[tex]\frac{P_1V_1}{T_1}=\frac{P_2V_2}{T_2}[/tex]

where,

[tex]P_1[/tex] = initial pressure of gas (STP) = 1 atm

[tex]P_2[/tex] = final pressure of gas = 99.2 kPa = 0.98 atm  (1kPa=0.0098atm)

[tex]V_1[/tex] = initial volume of gas  = 67000 L

[tex]V_2[/tex] = final volume of gas = ?

[tex]T_1[/tex] = initial temperature of gas (STP)  = 273K

[tex]T_2[/tex] = final temperature of gas = [tex]10.0^0C=(273+10)K=283K[/tex]

Now put all the given values in the above equation, we get:

[tex]\frac{1\times 67000}{273}=\frac{0.98\times V_2}{283}[/tex]

[tex]V_2=70872L[/tex]

Thus the volume is 70872 L

84. A salution of a substance x is used
of a
for
il Name the sulsstance 'x' and the
white kashing
write its farmula
il y Write the reaction the substance
la' named in il above with water.
of
dne

Answers

Answer:

Following are the answer to this question:

Explanation:

(1) Calcium oxide (CaO) is also referred to as quicklime. It is the solution for the substance used for whitewashing.  

Whenever it reacts with water ([tex]H_2O[/tex]) and absorbs carbon dioxide ([tex]CO_2[/tex]), it then formed calcium carbonate ([tex]CaCO_3[/tex]), which produced a hard laminate on the walls, to first be whitened by the production of calcium hydroxide (CaOH).  

(2) Slackened lime or calcium hydroxide arises whenever the fast limestone reacts with water.

[tex]CaO(s) + H_2O(l) \rightarrow Ca(OH)_2(aq).[/tex]

Which of the following best describes why a cruise ship floats?
A. It displaces an equal or greater amount of water than its own
weight.
B. It displaces more than half of its weight in water.
C. Its volume and mass are equal.
D. Its volume is greater than its mass.

Answers

Answer:

A. It displaces an equal or greater amount of water than its own weight.

Explanation:

Which of these observations are not explained by kinetic-molecular theory?

Answers

The question's incomplete unfortunately, which observations?

Answer:

At very low temperatures, gases expand less for a given pressure change than they do at high temperatures

NEED HELP! An experiment _____. must always be done in a laboratory is best done if only one variable is tested for at a time can be done only by direct observation must always be done in the field

Answers

Answer:

Chemically

in chemistry

Name two drying agents that can be use to dry hydrogen gas​

Answers

CaCl2, Na2SO4, MgSO4 are three drying agents that can be used to dry hydrogen gas

5. What volume would you need to dilute 0.2 L of a 15 M solution to obtain a 3 M
solution?

Answers

Answer:

IL

Explanation:

M_1 V_1 = M_2 V_2

M_1 = 15 M

V_1 = 0.2 L

M_2 = 3 M

V_2 = ?

15 x 0.2 = 3V_2

15 x 0.2 = 3

3 / 3V_2

1 L= V_2

1 L is the volume that would be needed to dilute 0.2 L of a 15 M solution to obtain a 3 M solution.

What is volume?

A measurement of three-dimensional space is volume. It is frequently expressed quantitatively in SI-derived units, other imperial units, or US customary units. Volume and the notion of length are connected. In contrast to how much space the container actually occupies, the overall size of a container is typically thought of as its capacity, or the quantity of fluid it could hold.

Volume was initially measured using naturally occurring vessels of a comparable shape and then with standardised containers. Arithmetic formulas can be used to quickly calculate the volume of several straightforward three-dimensional shapes.

Molarity₁×Volume₁=Molarity₂×Volume₂

15 x 0.2 = 3×Volume₂

15 x 0.2 = 3

3 / 3=Volume₂

1 L=Volume₂

Therefore, 1 L is the volume that would be needed to dilute 0.2 L of a 15 M solution to obtain a 3 M solution.

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Another chemistry question. Help me!
To prepare 250cm³ of standard solution of 1.0 mol dm-³ sodim carbonate Na2Co3​

Answers

Answer:

Molar mass Na2CO3 = 2*23 + 12 + 3*16 = 106 g/ mol

Mass of 1 mol Na2CO3 = 106 g

mass (Na2CO3) = 106g*250cm³/1000cm³ = 26.5 g

1) It is necessary because all Na2CO3 will be in the solution, and no Na2CO3 would be lost.

2) Because the solution that was formed after rinsing beaker contains Na2CO3.

3) Eyes should be on the level of calibration mark of the volumetric flask.

4) It is necessary to prevent evaporation of water, and changing , because of it, the concentration of the solution.

The minerals of aluminium include all of the following except
A. corundum
B. kaolin
C. Bauxite
D. Cryolite​

Answers

Bauxite I think , it’s probably C
It is cryolite because all the other 3 are forms of aluminum while cryolite is used to extract it

PLEASE HURRRYYYY

A buffer is made using HCO2Na. Which other substance should the buffer contain?

HCO2Li

HCO2H

NaNO3

HCl

Answers

Answer:

HCO₂H

Explanation:

A buffer is defined as the mixture between a weak acid and its conjugate base, or vice versa, in an aqueous solution.

The HCO₂Na (Sodium formate), is the conjugate base of formic acid, HCO₂H, a weak acid of pKa = 3.75.

Thus, to make a buffer using HCO₂Na, the other substance the buffer should contain is HCO₂H

Answer:

HCO₂H

Explanation:

so ...this is the question and I hope you get it right one​

Answers

Answer:

About 96 grams per mole

Explanation:

The chemical formula of ammonium carbonate is [tex](NH_4)_2CO_3[/tex]. This means that breakdown of moles of atom per mole of molecule is:

2 moles of nitrogen, with a molar mass of around 14

8 moles of hydrogen, with a molar mass of around 1

1 mole of carbon, with a molar mass of about 12

3 moles of oxygen, with a molar mass of about 16

The molar mass of ammonium carbonate is therefore:

2(14)+8(1)+1(12)+3(16)=28+8+12+48=about 96

Hope this helps!

2 Points
A student blows a whistle. In which direction do the air particles vibrate with
respect to the direction the sound wave travels?

A. Perpendicular to

B. Parallel to

C. At a 45 degree angel to

D. At an unpredictable angel

Answers

Answer:

parallel to

Explanation:

In parallel direction the air particles vibrate with respect to the direction the sound wave travels. The correct option is B.

What is sound wave?

A sound wave is the pattern of disturbance caused by the movement of energy as it propagates away from the source of the sound through a medium (such as air, water, or any other liquid or solid matter).

Sound waves are produced by object vibrations and pressure waves, such as a ringing cellphone.

Because sound waves are produced by compressions and rarefactions in the air, they are referred to as longitudinal waves. The air particles vibrate in a direction parallel to the propagation direction.

The particles in a longitudinal wave are displaced parallel to the direction of the wave. Compressions moving along a slinky are an example of longitudinal waves.

Air particles vibrate in a parallel direction to the direction of travel of the sound wave.

Thus, the correct option is B.

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can periodic table indicates occurrance of the elements, why?​

Answers

Answer: No

Explanation:

A periodic table can be defined as the table in which the row of chemical elements are present. All the elements of the row have same number of electron shells.

The arrangement of elements is based on atomic numbers, electron shell model and other chemical properties. The elements are placed in increasing order of atomic number.

This table does not give information about the occurrence of the elements.

What is Charles’s law? State the definition of the law in words. What are the assumptions of Charles’s law? Write mathematical equations that represent the law. What can you do with Charles’s law? Using a gas-filled balloon as an example, describe what happens to the gas molecules that behave according to Charles’s law.

Answers

Answer:

The volume of a given mas of a gas is directly proportional to the temperature if the pressure remains constant

V is directly proportional to T

V=1/T

V=constant/T

Explanation:

Charles law states that the volume occupied by a fixed amount of gas is directly proportional to its absolute temperature, if the pressure remains constant.

e.g., In winters as the temperature falls off, when you take a basketball outside in the ground the ball shrinks.

The mathematical equation that represents Charles law:

V₁/T₁ = V₂/T₂

where, V₁ = initial volume

T₁ = initial absolute temperature

V₂ = final volume

T₂ = final absolute temperature

The applications of Charles law has in daily life are:

Helium balloons shrinks in a cold weather.The capacity of the human lung decreases in winter season. This makes difficult for the athletes to perform in winter season and it also makes it difficult for people to go jogging.

A gas-filled balloon experiment:

If a balloon is filled with air, it will shrink when cooled and the balloon expands if heated. This happens because the air inside the balloon, which is a gas molecules, occupies a smaller volume when it is cool, and occupies  a larger volume when it is hot.

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How many grams of H2S is needed to produce 18.00g of PbS if the H2S is reacted with an
excess (unlimited) supply of Pb(CH3COO)2?

Answers

Answer:

2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an  excess (unlimited) supply of Pb(CH₃COO)₂

Explanation:

The balanced reaction is:

Pb(CH₃COO)₂ + H₂S → 2 CH₃COOH + PbS

By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction) they react and produce:

Pb(CH₃COO)₂: 1 moleH₂S: 1 moleCH₃COOH: 2 molesPbS: 1 mole

In this case,  to know how many grams of H₂S are needed to produce 18.00 g of PbS, it is first necessary to know the molar mass of the compounds H₂S and PbS and then to know how much it reacts by stoichiometry. Being:

H: 1 g/moleS: 32 g/molePb: 207 g/mole

The molar mass of the compounds are:

H₂S: 2* 1 g/mole + 32 g/mole= 34 g/molePbS: 207 g/mole + 32 g/mole= 239 g/mole

So, by stoichiometry they react and are produced:

H₂S: 1 mole* 34 g/mole= 34 gPbS: 1 mole* 239 g/mole=   239 g

Then the following rule of three can be applied: if 239 grams of PbS are produced by stoichiometry from 34 grams of H₂S, 18 grams of PbS from how much mass of H₂S is produced?

[tex]mass of H_{2} S=\frac{18 grams of PbS*34 grams of H_{2}S }{239 grams of PbS}[/tex]

mass of H₂S= 2.56 grams

2.56 grams of H₂S is needed to produce 18.00g of PbS if the H2S is reacted with an  excess (unlimited) supply of Pb(CH₃COO)₂

Can Chlorine be harmful to any of the earth’s ecosystems? If so how?

Answers

Answer:

Although chlorine itself usually does not cause environmental harm, it combines rapidly to form chemicals such as dioxins that pollute water, contaminate fish and transfer to humans and larger animals that eat the fish.

Explanation:

Name the following compound: CH3 – CH2 – CH2 – CH2 – CH3

Answers

Answer:

Pentane

Explanation:

PLS HELP ! 5.00 mL of a stock solution, containing 0.200 M of Na3PO4 was pipetted into a 25.00 mL volumetric flask and made up to the calibration mark with deionised water. A serial dilution was carried out for another two times to obtain the final solution of desired concentration. Calculate the concentration of the final solution, express in ppm (by volume).

Answers

Answer:

262 ppm of Na₃PO₄

Explanation:

In a dilution, the concentration of the initial solution is decreased. When you take 5.00mL of the solution that is diluted to 25.0mL The solution is diluted 25/5 = 5 times

If you make another two serial dilutions the final solution wil decrease its concentration 5*5*5 = 125 times

As original solution containing 0.200 M of Na3PO4, the final solution will have a concentration of:

0.200M / 125 = 1.6x10⁻³M

Molarity is defined as the ratio between moles and liters. 1.6x10⁻³ moles of Na3PO4 in 1L are:

1.6x10⁻³mol ₓ (164g/mol) = 0.262g Na₃PO₄ / L

Assuming density of Na3PO4 as 1g/mL the concentration of the solution is:

0.262mL Na₃PO₄ / L

As 1mL = 1000μL:

262μL Na₃PO₄ / L

μL of solute per L of solution is equal to ppm, that means the solution has:

262 ppm of Na₃PO₄

URGENT!!!!
An ordered list of chemical substances is shown.

Which substances in the list can be some of the reactants and products in the same combustion reaction? (4 points)

Select one:
a. 1, 2, and 3
b. 2, 3, and 6
c. 1, 4, and 5
d. 1, 2, and 5

Answers

Answer : The correct option is (b) 2, 3, and 6

Explanation :

Combustion reactions: It is defined as the reactions in which a hydrocarbon reacts with oxygen gas to produce carbon dioxide and water.

A balanced chemical equation is defined as the equation in which total number of individual atoms on the reactant side is equal to the total number of individual atoms on product side.

The general chemical equation for the combustion is as follows:

[tex]C_xH_yO_z+O_2\rightarrow CO_2+H_2O[/tex]

where, 'x', 'y' and 'z' are the subscripts of Carbon, hydrogen and oxygen respectively.

The reactants and products in the same combustion reaction are [tex]O_2[/tex] and [tex]CO_2,H_2O[/tex] respectively.

Hence, the correct option is (b) 2, 3, and 6

Keeping in mind the rules for significant dig-
its, what is the product of 0.6906 m and 4.03
m?

Answers

Answer:

2.78

Explanation:

When multiplying, your answer will have the same amount of sig figs as the multicand or multiplier that has the lower number of sig figs. In this case, 4.03 is the one with the lowest number of sigs figs, which is 3 sig figs, so the answer should have 3 sig figs, so the answer is 2.78.

Jaiden is writing a report about the structure of the atom. In her report, she says that the atom has three main parts and two subatomic particles. Do you agree with her? Why or why not?

Answers

Answer:

The smallest constituent of an element is termed as an atom. According to Jaiden, an atom comprises two subatomic particles and three prime parts, however, this is incorrect as an atom comprises three subatomic particles and two main parts. The three subatomic particles are the protons, electrons, and neutrons. All these parts are smaller in comparison to an atom, thus, they are considered as subatomic particles.  

To be considered as an atom, an atom is needed only electrons and neutrons, like hydrogen exhibit one electron and one proton. On the other hand, the overall charge of the atom is not affected by the presence of neutrons, it is the subatomic particle that only enhances the mass of the atom.  

Answer:

I disagree with her because an atom has two main parts: the nucleus and the electron cloud. Atoms have three subatomic particles: protons, neutrons, and electrons.

Explanation:

If 119.5 g of iron is mixed with 279.50 g of copper (II) nitrate, what is the limiting reagent for the reaction?

Answers

Answer:

Copper ii nitrate is the limiting reagent

Explanation:

The first thing to write here is the equation of reaction;

Fe + Cu(NO3)2 ——> Fe(NO3)2 + Cu

When we talk of limiting reagent, we mean the reactant that is totally consumed upon the completion of the chemical reaction

To get the limiting reagent, we can know this by calculating the mass of a specific product formed from each of the masses of the reactants

Now, we can use the amount of copper solid deposited by each of the reactants to know the limiting reagent here.

Since the mole ratio in all cases is 1 to 1, this will be easy

For the iron, the number of moles reacted is mass of iron/ atomic mass of iron

That would be 119.5/56 = 2.134 moles

Now since the mole ratio is 1 to 1, 2.134 moles of copper will be formed

Thus, the mass of copper produced from the iron will be number of moles * atomic mass of copper = 2.134 * 64 = 136.57g

Now from the nitrate, the number of moles is

mass mixed/ molar mass of copper nitrate

molar mass of copper nitrate is 188g/mol

number of moles is thus 279.5/188 = 1.487 moles

Since the mole ratio is 1 to 1, it means that the number of moles of copper produced too is 1.487 moles

The mass of copper produced from this is number of moles of copper * atomic mass of copper

That will be 1.487 * 64 = 95.15g

Now, since the copper nitrate produces less amount of copper solid, it is the the reagent to be consumed first and thus it is our limiting reagent

Other Questions
A man driving a car leaves a point A drives up to 32.5 km in a direction of 070. A cyclist leaves the same point in a direction 130 travelling. After some few hours both drivers are 80 km apart. Use this information to answer 3 questions. (1). What is the distance covered by the cyclist at this time in 2 d.p. (2). Find the bearing of Cyclist from the Car. correct to 1 d.p. (3). Find the shortest distance between the car and the line of path of the cyclist, in 2 d.p. 84. A salution of a substance x is usedof aforil Name the sulsstance 'x' and thewhite kashingwrite its farmulail y Write the reaction the substancela' named in il above with water.ofdne pls anwers the question pls it has pictures as well pls pls pls pls pls pls pls Why did Missouris attempt to enter the Union create tensions between the sections?A. Missouri wanted to enter as a slave state, which would upset the balance of power between slave and free states in the Senate.B. Northern politicians wanted to make Missouri part of Illinois for its rich farmland, but southern politicians opposed this.C. Missouri wanted to join into one state with Arkansas, which would have created a large slave state that northern states opposed.D. Southern politicians wanted to build a railroad from the South to Missouri, but northern states wanted to connect the state with a canal. A particle initially located at the origin has an acceleration of = 1.00 m/s2 and an initial velocity of i = 6.00 m/s. (a) Find the vector position of the particle at any time t (where t is measured in seconds). ( t + t2 ) m (b) Find the velocity of the particle at any time t. ( + t ) m/s (c) Find the coordinates of the particle at t = 4.00 s. x = m y = m (d) Find the speed of the particle at t = 4.00 s. Suppose the market for pizzas is unregulated. That is, pizza prices are free to adjust based on the forces of supply and demand.If a shortage exists in the pizza market, then the current price must be.............than the equilibrium price. For the market to reach equilibrium, you would expect................ For males in a certain town, the systolic blood pressure is normally distributed with a mean of 125 and a standard deviation of 10. What percentage of males in the town that have a systolic blood pressure higher than 125, to the nearest tenth? Find the x-intercept and y-interceptfrom the following linear equation:6x 9y = 54x - intercept ([?], [])y - intercept ([],[]) Verify the following identity: (csc theta -cot theta )/(sec theta -1) A. sec theta B. cos theta C. cot theta D. sin theta Please help with this Men such as John Lyly, Thomas Lodge, George Gascoigne, and Sir Philip Sidney wrote early _____in proseA. Biographies B. Fiction C. Nonfiction Identified the characteristics of major character and minor character Exercise 14-5 (Algo) Bonds; issuance; effective interest; financial statement effects [LO14-2] Myriad Solutions, Inc. issued 12% bonds, dated January 1, with a face amount of $390 million on January 1, 2021, for $348,683,634. The bonds mature on December 31, 2030 (10 years). For bonds of similar risk and maturity the market yield is 14%. Interest is paid semiannually on June 30 and December 31. Required: Calculate the amounts related to the bonds that Myriad would report in its financial statements. (Round your answers to the nearest whole dollar.) Express 7212 in the exponential from which story premise is the best example of magical realism?A. Duke has too win the snowboarding competition in order to save his schoolB. A horse who was once a movie star struggles to bring his career back to lifeC. A wizard plunders an ancient dungeon for the secret of how to tame dragonsD. Aliens from outer space invade earth and only Capybara man can stop them Find the slope of a line through the points (-1,-9) and (4,-2). Barry has $30.00 to spend on soft drinksfor a party. A case of soft drinks costs$4.65. Which inequality can be used to find how many cases (c) of soft drinksBarry can purchase? if teta is an angle in right angle triangle if tan teta = 3/4 then find sin teta? The mean age of the employees at a large corporation is 35.2 years, and the standard deviation is 9.5 years. A random sample of 4 employees will be selected. What are the mean and standard deviation of the sampling distribution of the sample mean for samples of size 4 ? A. The mean is 35.2, and the standard deviation is 9.5. B. The mean is 35.2, and the standard deviation is 9.5/4. C. The mean is 35.2, and the standard deviation is 9.5/2. D. The mean is 35.2/4, and the standard deviation is 9.5/4. E. The mean is 35.2/2, and the standard deviation is 9.5/2. Fortune telling rhymes based on the day when a child was born originated in England around the 1500s. Many superstitions existed regarding the day of the week when a child was born. Children fortunes, personalities, and temperaments were considered to be regulated by that day. What are the cases in the poem