Notice that the value 12.01 grams of natural carbon is the same as the atomic mass value (12.01 amu). It also tells us that 20.34 grams of aluminum contains exactly 6.022 x 1023 atoms of aluminum.
✅
So, the answer is A) 6.02 x 10^23 atoms
IamSugarBee
Answer:
Option A: 6.03 * 10^23 atoms
What happens when the sound waves released by a bat hit an object?
O The sound waves are diffused.
O The sound waves are reflected.
O The sound waves are refracted.
O The sound waves are absorbed.
Answer:
O The sound waves are reflected.
Explanation:
When sound waves released by a bat hits an object, the sound waves are reflected back.
Bats used sound reflection for echolocation to determine the position of nearby objects.
Also, they use it to determine the shape and size of objects.
The mechanism where bats use sound to determine location is known as echolocation. The bat picks up the reflected sound and projects the location of their targets.Answer:
B
The sound waves are reflected.
Explanation:
Sam washed his favorite pair of jeans. He hung the wet jeans on a clothesline outside. An hour later the jeans were dry.
Which answer best describes that happened to the water that was in the wet jeans an hour later?
State your answer and provide an explanation for your answer
A It soaked into the ground.
B It disappeared and no longer exists.
C It is in the air in an invisible form.
D It moved up to the clouds.
E It chemically changed into a new substance.
F It went up to the Sun.
G It broke down into atoms of hydrogen and oxygen.
Please help D:
Answer:
THe sun evapored the water and the wind helped dry it to.
Explanation:
PLEASE HELP!! 74 POINTS
An igneous rock has small, dark crystals. Which statement also accurately describes this rock?
It is an intrusive rock.
It has a coarse texture.
It was found on Earth’s surface.
It was formed from slow cooling.
---------------------------------------------------------
Which is one factor that contributes to the formation of polar, temperate, and tropical zones?
the angle of the Sun’s rays
the direction of seasonal winds
the presence of prevailing winds
the movement of wind near a mountain
Answer:
It was formed from slow cooling.
the angle of the Sun’s rays
Explanation:
Answer:
D. It was formed from slow cooling.
Calculate the mass of dinitrogen tetroxide(N2O4) that contains a billion oxygen atoms. Be sure your answer has a unit symbol if necessary, and round it to significant digits.
Answer:
23 * 10^ 9 atoms of oxygen
Explanation:
From the molecular formula of dinitrogen tetraoxide;
molar mass of dinitrogen tetraoxide = 92 g/mol
hence;
92 g of dinitrogen tetraoxide contains 4 atoms of oxygen
x g of dinitrogen tetraoxide will contain 1 * 10^ 9 atoms of oxygen
x = 92 * 1 * 10^ 9/4
x =23 * 10^ 9 atoms of oxygen
Suppose a student needs to standardize a sodium thiosulfate, Na2S2O3,Na2S2O3, solution for a titration experiment. To do so, he or she will react it with a solution of iodine. The student adds a 1.00 mL1.00 mL aliquot of 0.0200 M KIO30.0200 M KIO3 solution to a flask, followed by 3 mL3 mL of distilled water, 0.2 g0.2 g of solid KI,KI, and 1 mL H2SO4.1 mL H2SO4. The student then titrates the solution with sodium thiosulfate solution in order to determine the exact concentration of Na2S2O3.Na2S2O3. The end point of the titration is reached after 0.90 mL0.90 mL of Na2S2O3Na2S2O3 is dispensed from a microburet. What is the concentration of the standard sodium thiosulfate solution?
Answer:
0.133
Explanation:
reaction between KIO3 and KI in acidic medium
IO3⁻ +5I⁻ +6h⁺ → 3I₂ + 3H₂O
I₂ reacts with thiosulphate
NaS₂O₃ → 2Na⁺ + S₂O₃²⁻
net reaction
IO⁻₃ + 6H⁺ + 6S₂O₃³⁻ → I⁻ + 3S₄O₆²⁻ + 3H₂O
mole of KIO₃
= molarity x volume
[tex]\frac{0.02mol}{L} *0.01L[/tex]
= 0.00002mol
a mole of KIO₃ has reaction with 6 mol of S₂O₃²⁻
= 2x6x10⁻⁵
= 0.00012 mol
volume = 0.90 ml
1 ml = 0.001L
0.90ML = 0.0009L
to get concentration,
molarity/volume
= 0.00012/0.0009
= 0.133m
The concentration of the standard sodium thiosulfate solution is ; 0.133
The net chemical reaction equation
IO₃⁻ + 6H⁺ + 6S₂O₃³⁻ ----> I⁻ + 3S₄O₆²⁻ + 3H₂O
First step : Determine the moles of KIO₃
number of moles = molarity * volume
= 0.02 mol / L * 0.01 L
= 0.00002 mol
From the net chemical reaction equation
one ( 1 ) mole of KIO₃ reacts with 6 moles of S₂O₃²⁻
∴ number of moles in the reaction = 6 * 0.00002 = 0.00012 mol.
Final step : Determine the concentration of sodium thiosulfate solution
Given Volume = 0.90 ml = 0.0009 L
∴ concentration of sodium thiosulfate solution
= 0.00012 / 0.0009 = 0.133
Hence we can conclude that The concentration of the standard sodium thiosulfate solution is ; 0.133
Learn more : https://brainly.com/question/15271672
Sulfur dioxide and oxygen react to form sulfur trioxide during one of the key steps in sulfuric acid synthesis. An industrial chemist studying this reaction fills a 50.0L tank with 14. mol of sulfur dioxide gas and 2.6 mol of oxygen gas, and when the mixture has come to equilibrium measures the amount of sulfur trioxide gas to be 1.6 mol. Calculate the concentration equilibrium constant for the reaction of sulfur dioxide and oxygen at the final temperature of the mixture. Round your answer to 2 significant digits.
Answer:
Explanation:
From the given information:
The equation for the reaction can be represented as:
[tex]2SO_2 + O_2 \to 2SO_3[/tex]
The I.C.E table can be represented as:
2SO₂ O₂ 2SO₃
Initial: 14 2.6 0
Change: -2x -x +2x
Equilibrium: 14 - 2x 2.6 - x 2x
However, Since the amount of sulfur trioxide gas to be 1.6 mol.
SO₃ = 2x,
then x = 1.6/2
x = 0.8 mol
For 2SO₂; we have 14 - 2x
= 14 - 2(0.8)
= 14 - 1.6
= 12.4 mol
For O₂; we have 2.6 - x
= 2.6 - 1.6
= 1.0 mol
Thus;
[SO₂] = moles / volume = ( 12.4/50) = 0.248 M ,
[O₂] = 1/50 = 0.02 M ,
[SO₃] = 1.6/50 = 0.032 M
Kc = [SO₃]² / [SO₂]² [O₂]
= ( 0.032²) / ( 0.248² x 0.02)
= 0.8325
Recall that; the equilibrium constant for the reaction [tex]2SO_2 + O_2 \to 2SO_3[/tex] = 0.8325;
If we want to find:
[tex]SO_2 + \dfrac{1}{2}O_2 \to SO_3[/tex]
Then:
[tex]K_c = (0.8325)^{1/2}[/tex]
[tex]\mathbf{K_c = 0.912}[/tex]
Since no temperature is given to use in the question, it will be impossible to find the final temperature of the mixture.
Item 10
What color do acids turn litmus paper?
yellow
red
pink
blue
Answer:
red
Explanation:
blue litmus paper turns red under acetic conditions and red lettuce paper turns blue under basic and alkaline conditions with the color change occurring over the PH range the neutral litmus paper is purple
The answer is red.
took the test.
You are trying to confirm that your bottle of hydrochloric acid is supposedly 1.0 M, as labeled. You decided to perform a titration with 1.3 M sodium hydroxide and 100 mL of your hydrochloric acid. You expect to use 77 mL of sodium hydroxide to neutralize the acid, but in the experiment it actually took 89.13 mL of NaOH to reach the endpoint. What is the actual concentration of the hydrochloric acid?
Answer:
The actual concentration of the hydrochloric acid is 1.2M
Explanation:
The formula to be used here is that of concentration (popularly used during titration);
CₐVₐ/CbVb =nₐ/nb
where Cₐ is the concentration of acid (supposed to be 1.0 M but unsure)
Vₐ is the volume of acid (100 ml)
Cb is the concentration of base (1.3 M)
Vb is the volume of base (89.13 ml)
nₐ is the volume of acid
nb is the volume of base
The equation for the reaction described in the question is
HCl + NaOH ⇒ NaCl + H₂O
we can see from the above equation the ratio of the number of moles for both the acid and the base is 1:1
Thus;
Cₐ × 100/1.3 × 89.13 =1/1
Cₐ = 1.3 × 89.13/100
Cₐ = 1.2M
The actual concentration of the hydrochloric acid is 1.2M
Now
Selec
BI
Toda
OOOOOO
How and why do ionic bonds form? Check all of the boxes that apply
lonic bonds form between metal atoms and other metal atoms.
Ionic bonds form between metal atoms and nonmetal atoms
The more electronegative atoms transfer one or more electrons to the less electronegative atom
The less electronegative atoms transfers one or more electrons to the more electronegative atom,
The metal atom forms a cation and the nonmetal atom forms an anion
The attraction between ions with the same charge forms an ionic bond,
The attraction between ions with an opposite charge forms an ionic bond.
BLO
I lo
DONE
Elo
Yous
Answer:
✔️Ionic bonds form between metal atoms and nonmetal atoms.
✔️The less electronegative atoms transfers one or more electrons to the more electronegative atom
✔️The metal atom forms a cation and the nonmetal atom forms an anion.
✔️The attraction between ions with an opposite charge forms an ionic bond.
Explanation:
Ionic bond refers to the bond formation which occurs when there is complete and permanent transfer of electrons from one metal atom to another non-metal atom. The metals, which are electropositive (less electronegative) loose their electrons while the non-metals, which are less electropositive (more electronegative) gain the electrons.
When the metal atom looses electrons, they form cations(become positively charged) while non-metal atom forms anions (become negatively charged). When the opposite charges attract each other, they form ionic bond.
Answer:
✔️ Ionic bonds form between metal atoms and nonmetal atoms.
✔️ The less electronegative atoms transfers one or more electrons to the more electronegative atom.
✔️ The metal atom forms a cation and the nonmetal atom forms an anion.
✔️ The attraction between ions with an opposite charge forms an ionic bond.
Using Gizmo ,describe the main use for each fuel Coal: Petroleum: In each case, what is the end product of burning the fossil fuel,and where does it go? Help is for today
Answer:
See explanation
Explanation:
Coal is primarily used for electricity generation. The burning of coal leads to emission of gases such as oxides of carbon, oxides of sulphur, oxides of nitrogen and water vapour. All these go straight into the atmosphere.
Petroleum is primarily used as transportation fuels. The burning of petroleum oils mostly leads to the emission of oxides of carbon and sulphur together with water vapour into the atmosphere.
The idea that the earth is divided into a number of small plates that float on the mantle and slide,collide,and slip past each other. Law or Theories
Answer:
Theories
Explanation:
It is theories because it was a generalistee abstract or thinking generalising the principle of fact about Earth tectonic plates ,it was formulated and concluded as plate tectonic theories after many findings. The theories conclude that the Earth has an outer layer called lithosphere and lies overly a plastic layer called asthenosphere. The lithosphere is divided into several plates and they move close to each other where they diverge, converge or slip over one another.
What is an extremophile? What domain is known for these organisms?
Extremophiles are bacteria, archaea, as well as eukarya across all three domains of life. Cells make up every organisms.
What is Extremophiles?Extremophiles contain bacteria, archaea, as well as eukarya from all three domains of life.
What is organisms ?Any organic, biological system which works as a separate entity was referred to as an organism.
Extremophiles are organisms that can survive in harsh settings, such as those with high temperatures, radiation, salt, or pH levels. In the planet's evolutionary development, several creatures have been ecologically dominating.
To know more about Extremophiles and organisms.
https://brainly.com/question/12825206
#SPJ2
What are the factors affecting your limitations? How about possibilities?
Explanation:
My physiological make-up that governs the attributes I have and my climate, i.e. the conditions I have, are the variables influencing my limits. Biological make-up also regulates my prospects when they depend on my attributes, i.e. my ability and my environment , i.e. the conditions under which I am. This has been shown by experiments on twins, that our limits and opportunities are controlled by both genetics and environment.
Which of the following reactions would you expect to produce the most energy?
A. Nuclear fusion of two hydrogen isotopes.
B. Combustion of hydrogen gas.
C. Combination of a strong acid and a strong base.
D. Burning a large hydrocarbon, such as oil.
Answer:
A
Explanation:
Nuclear fusion is a much more powerful reaction than any of the others.
Nuclear fusion of two hydrogen isotopes would expect to produce the most energy. Therefore, option (A) is correct.
What is nuclear fusion?Nuclear fusion can be defined as when two or more nuclei fuse together to form a single heavier nucleus. In this reaction, the matter is generally not conserved due to some of the mass of the nuclei being converted to energy.
For nuclear fusion, the nuclei must be brought closer to the reaction occurring. Each star in the universe, including sun, is shining due to nuclear fusion reactions. They produce large amounts of energy in this process.
In the Sun's core, hydrogen nuclei are get transformed into helium nuclei which are known as nuclear fusion. It takes place when four hydrogen nuclei fuse into each helium nucleus. During the Nuclear fusion process, some of the mass of hydrogen nuclei is transformed into energy.
Therefore, nuclear fusion is where hydrogen atoms combined to form helium to produce the most energy.
Learn more about nuclear fusion, here:
brainly.com/question/12701636
#SPJ2
A bomb calorimeter with a heat capacity of 837 J∘C contains 745 g of water. It burns 2.50 g C8H18 resulting in the temperature going from 15.0∘C to 33.8∘C. What is the value of the heat transferred (in kilojoules) by the reaction from the perspective of the system?
Answer:
74.3kJ are transeferred
Explanation:
In the bomb calorimeter, the burning of C₈H₁₈ is producing heat that is been absorbed for the calorimeter and the water.
Heat absorbed calorimeter:
837J/°C * (33.8°C-15.0°C) = 15735.6J
Heat absorbed water:
C*m*ΔT
C specific heat of water (4.184J/g°C), m is mass of water (745g), and ΔT change in temperature (33.8°C - 15°C = 18.8°C)
4.184J/g°C*745g*18.8°C = 58601.1J
Heat released by the reaction:
15735.6J + 58601.1J = 74336.7J
74.3kJ are transeferred
Assuming that a cheese sandwich consists of 2 slices of bread and 3 slices of cheese, determine the number of whole cheese sandwiches that can be prepared from 44 slices of bread and 63 slices of cheese.
Answer:
21 is the max but with the bread ypu could make 22 if you had 3 more cheese
I NEED HELP ASAP
Types of Cells
1) I have a cell membrane?
PROKARYOTE
EUKARYOTE *******
BOTH
2)I have a nucleus *
PROKARYOTE*****
EUKARYOTE
BOTH
3)I am a bacteria *
PROKARYOTE
EUKARYOTE
BOTH
1) Both cells have a cell membrane.
2) A nucleus is present in only Eukaryote cells.
3) I'm pretty sure Prokaryote cells are bacteria.
Hope this helps!! :)
The # of electrons in S2- -34 is
Answer:
The answer is 16
Explanation:
When 60 mL of 0.22 M NH4Cl is added to 60 mL of 0.22 M NH3, relative to the pH of the 0.10 M NH3 solution the pH of the resulting solution will:____________.
Answer:
Will be more acidic
Explanation:
The equilibrium of NH3 in water is:
NH3(aq) + H2O(l) ⇄ NH4⁺(aq) + OH⁻(aq).
Where equilibrium constant, Kb, is:
Kb = 1.85x10⁻⁵ = [NH4⁺] [OH⁻] / [NH3]
From 0.10M NH3, the reaction will produce X of NH4⁺ and X of OH⁻ and Kb will be:
1.85x10⁻⁵ = [X] [X] / [0.10M]
1.8x10⁻⁶ = X²
X = 1.34x10⁻³ = [OH⁻]
As pOH = -log[OH⁻] = 2.87
And as pH = 14 - pOH
pH of the 0.10M NH3 is 11.13
Now, to find the pH of the NH4Cl and NH3 we need to use H-H equation for bases:
pOH = pKb + log [NH4⁺] / [NH3]
Where pKb is -log Kb = 4.74 and [] are moles of both compounds.
Moles of [NH4⁺] = [NH3] = 60mL, 0.060L*0.22M = 0.0132moles:
pOH = 4.74 + log [0.0132] / [0.0132]
pOH = 4.74
pH = 14 - 4.74 = 9.26
That means the pH of the resulting solution will be more acidic
Sodium is located above potassium in Group 1 of the periodic table. If a potassium ion has a charge of +1, what is the charge on a sodium ion?
A. -1
B 0
C. +1
D +2
Answer:
C
Explanation:
It will be the same. That's what moving down a column means. The properties are going to be quite similar.
Which of the following rock will form if it is broken into sediment then emulsified over a long period of time?
Sedimentary rock
Magma rock
Metamorphic rock
Igneous rock
Which of the following represents the equation for volume?
L x H
L x W
L x W x H
W x H
Answer:
L× W×H
Please mark me as brainlist.Answer:
The correct answer is L x W x H :)
Object A has a mass of 12g and a volume of 8cm3. object B has a mass of 20g and a volume of 8cm3 . which object has a greater density and by how much
Answer:
Object B has a density of 2.5 g/cm³ which is greater than object A by 1 g/cm³
Explanation:
Since we know that the formula for density is d=m/v, we can divide each mass by its corresponding volume to find the densities
12/8=1.5
20/8=2.5
So we know that object B has a greater density than object A by 1 g/cm³ (gram per cubic centimeter). Also the standard unit for density is kilograms per cubic meter but I used gram per cubic centimeter since they were the given units. 1cm=100m, 1000g=1km
Lamark goes to a bowling alley to test his belief that rolling a bowling ball slowly will result in knocking down more pins. He gently rolls his bowling ball towards the bowling pins lined up at the end of the lane. The bowling ball stops in the middle of the lane without striking the pins. Which statement below best explains what happened?
Answer:
The ball's kinetic energy is transforming to potential energy.
Explanation:
the ball is stopping resulting in potential energy
What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH
Answer:
a) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = pKa?
Step 1: Data given
Volume of HC2H3O2 = 1.0 L
Molarity of HC2H3O2 = 1.8 M
Ka = 1.8*10^-5
ph = pK = -log(1.8*10^-5) = 4.74
Step 2:
Use the Henderson-Hasselbalch equation.
pH = pKa + log(A-/HA)
4.74 = 4.74 + log(A-/HA)
0 = log(A-/HA)
A-/HA = 1
Consider X = moles of NaOH added (and moles of A- formed)
Remaining moles of HA = 1.8 - X
moles of A- = X
HA = 1.8 - X
X/(1.8-X) = 1
X =0.9
We have to add 0.9 mole NaOH to 1.0 L of 1.8 M HC2H3O2
To control we can do the following equation:
4.74 = 4.74 + log(0.9/0.9) = 4.74
b) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 4.00?
Step 1: Data given
Volume of HC2H3O2 = 1.0 L
Molarity of HC2H3O2 = 1.8 M
Ka = 1.8*10^-5
ph = 4
Step 2:
Use the Henderson-Hasselbalch equation.
pH = pKa + log(A-/HA)
4 = 4.74 + log(A-/HA)
-0.74 = log(A-/HA)
A-/HA = 0.182
Consider X = moles of NaOH added (and moles of A- formed)
Remaining moles of HA = 1.8 - X
moles of A- = X
HA = 1.8 - X
X/(1.8-X) = 0.182
X =0.277
We have to add 0.277 mole NaOH to 1.0 L of 1.8 M HC2H3O2
To control we can do the following equation:
4 = 4.74 + log(0.277/1.523)
c) What quantity (moles) of NaOH must be added to 1.0 L of 1.8 M HC2H3O2 to produce a solution buffered at pH = 5.00
Step 1: Data given
Volume of HC2H3O2 = 1.0 L
Molarity of HC2H3O2 = 1.8 M
Ka = 1.8*10^-5
ph = 5
Step 2:
Use the Henderson-Hasselbalch equation.
pH = pKa + log(A-/HA)
5 = 4.74 + log(A-/HA)
0.26 = log(A-/HA)
A-/HA = 1.82
Consider X = moles of NaOH added (and moles of A- formed)
Remaining moles of HA = 1.8 - X
moles of A- = X
HA = 1.8 - X
X/(1.8-X) = 1.82
X =1.16
We have to add 1.16 mole NaOH to 1.0 L of 1.8 M HC2H3O2
To control we can do the following equation:
5 = 4.74 + log(1.16/0.64) = 5
Explanation:
Calculate the freezing point of a solution containing 10 grams of KCl and 1100.0 grams of water. The molal freezing point depression constant (Kf) for water is 1.86
Answer:
- 0.454 °C
Explanation:
From the given information:
The mass of KCl = 10 grams
The molar mass of KCl = 74.55 g/mol
The molality can be calculated as:
[tex]Molality \ m = \dfrac{mass \ of \ KCl \times 1000}{molar \ mass \ of \ KCl \times 1100.0}[/tex]
[tex]Molality \ m = \dfrac{10 \ g \times 1000}{74.55 \ g/mol \times 1100.0}[/tex]
Molality m = 0.1219 M
For freezing point depression;
[tex]\Delta T_R = i \times k_f \times m[/tex]
The van't Hoff's Factor (i) for KCl = 2
The molar depression of freezing point constant [tex]k_f[/tex] = 1.86° C/m
∴
[tex]\Delta T_R = 2 \times 1.86 \times 0.1219[/tex]
[tex]\mathbf{\Delta T_R = 0.454^0\ C }[/tex]
However, the freezing point of water is known to be = 0°C
Therefore, the freezing point of the solution
= 0 °C - 0.454 °C
= - 0.454 °C
Define dynamic equilibrium.
a) no reactants react no products are formed the rate of the forward reaction
b) is faster than the rate of the reverse reaction the rate of the reverse reaction
c) is faster than the rate of the forward reaction the rate of the forward reaction
d) equals the rate of the reverse reaction
Answer:
d) The rate of forward reaction equals the rate of the reverse reaction
Explanation:
A dynamic equilibrium is attained when the rate of forward reaction is the same as reverse reaction. It occurs majorly in a reversible reaction. Thus, no change occurs in the reaction.
The process can be control by the immediate removal of the product as it is formed. This ensure that the reaction stops when all reactants are used up.
an area of high pressure occurs when
Answer:
A high-pressure area, high, or anticyclone, is a region where the atmospheric pressure at the surface of the planet is greater than its surrounding environment. Winds within high-pressure areas flow outward from the higher pressure areas near their centers towards the lower pressure areas further from their centers.
Explanation:
Calculate the number of moles of barium chloride in 427g of a 3.17%by mass barium chloride solution?a) 6.5x10^02molb) 7.83x10^02molc) 4.31x10^02mold) 7.81x10^02mole) 4.27x10^02mol
Answer:
The answer is "Option a".
Explanation:
Multiply the mass of the solutions by 3.17% to get the mass of [tex]BaCl_2[/tex]:
[tex]\to 427 \ g \times 0.0317 = 13.56\ g[/tex]
Divide this mass with BaCl2's molecular concentration to acquire the mole ratio:
[tex]molar mass = 208.24 \frac{g}{mol}\\\\moles = \frac{13.56}{208.24} = 0.065 \ moles \\\\[/tex]
[tex]= 6.5 \times 10^{-2} \ moles[/tex]
A 427 g sample is 3.17% by mass barium chloride contains 6.5 × 10⁻² moles of BaCl₂.
A 427 g sample is 3.17% by mass barium chloride, that is, there are 3.17 g of barium chloride per 100 g of sample.
The mass of barium chloride in 427 g of the sample is:
[tex]427gSample \times \frac{3.17gBaCl_2}{100gSample} = 13.5gBaCl_2[/tex]
We can calculate the number of moles in 13.5 g of barium chloride using its molar mass (208.23 g/mol).
[tex]13.5 g \times \frac{1mol}{208.23g} = 6.5 \times 10^{-2} mol[/tex]
A 427 g sample is 3.17% by mass barium chloride contains 6.5 × 10⁻² moles of BaCl₂.
Learn more: https://brainly.com/question/12127540
Please select the word from the list that best fits the definition
Represents a range of responses to a question:
Caption
Legend/Key
Scale
Answer:
The answer is B(scale)
Explanation:
Since the question asked about a range, the scale would be the most logical answer since scales are used to measure.
Answer:
the answer is C.
Explanation: