Krypton occupies 10.8 L at a pressure of 0.38 atm. Find the volume, in liters, of the krypton when the pressure is increased to 1.6 atm at the same temperature.

Answers

Answer 1

Answer:

New volume V2 = 2.565 L

Explanation:

Given:

Old volume V1 = 10.8 L

Old pressure P1 = 0.38 atm

New presuure P2 = 1.6 atm

Find:

New volume V2

Computation:

P1V1 = P2V2

So,

10.8 x 0.38 = V2 x 1.6

New volume V2 = 2.565 L


Related Questions

I'LL MARK YOU BRAINLIEST! Please help me balance these chemical reactions. (I'M NOT IN COLLEGE, I'M IN 10TH GRADE) Please help me​

Answers

Answer:

1. H2 + Cl2 => 2HCl

2. Na2S + 2HCl => 2NaCl + H2S

3. 6HCl + 2Al => 2AlCl3 + 3H2

4. C3H8 + 5O2 => 3CO2 + 4H2O

5. C6H12O6 + 6O2 => 6CO2 + 6H2O

6. 4C12H23O11 + 49O2 => 48CO2 + 46H2O

7. 4NH3 + 7O2 => 4NO2 + 6H2O

8. 2Mg + 02 => 2MgO

hope it helps

What is the molar mass of Ammonium Carbonate?

Answers

Explanation:

Molar mass

96.09 g/mol

glad to help....

What type of reaction
the following chemical reaction?
2C2H4O2 → C4H6O3 + H2O

Answers

This type of chemical reaction is Decomposition

1. Calculate how many moles of glycine are in a 130.0-g sample of glycine.2. Calculate the percent nitrogen by mass in glycine.

Answers

Answer:

[tex]n=1.732mol[/tex]

[tex]\% N=18.7\%[/tex]

Explanation:

Hello!

In this case, since the molecular formula of glycine is C₂H₅NO₂, we realize that the molar mass is 75.07 g/mol; thus, the moles in 130.0 g of glycine are:

[tex]n=130.0g*\frac{1mol}{75.07 g}\\\\ n=1.732mol[/tex]

Furthermore, we can notice 75.07 grams of glycine contains 14.01 grams of nitrogen; thus, the percent nitrogen turns out:

[tex]\% N=\frac{14.01}{75.07}*100\% \\\\\% N=18.7\%[/tex]

Best regards!

How many moles are there in 2.30 x 1024 atoms of silver?

Answers

Answer:

Step 1 should be convert atoms to moles (n). Step 2 should be convert moles (n) to mass (m).

Step 1

Use dimensional analysis to convert the number of atoms to moles.

1 mole atoms = 6.022 × 10²³ atoms

n(Ag) = 2.3 × 10²⁴ Ag atoms × (1 mol Ag/6.022 × 10²³ Ag atoms) = 3.8193 mol Ag

Step 2

Convert the moles of Ag to mass.

mass (m) = moles (n) × molar mass (M)

n(Ag) = 3.8193 mol Ag

M(Ag) = atomic weight on the periodic table in g/mol = 107.868 g Ag/mol Ag

m(Ag) = 3.8193 mol × 107.868 g/mol = 412 g Ag = 410 g Ag rounded to two significant figures

The mass of 2.3 × 10²⁴ Ag atoms is approximately 410 g.

Explanation:

The number of moles that are present is 2.3 × 10²⁴ atoms of silver are 3.8193 moles that can be determined using Avogadro's law.

The calculation for number of moles:

One mole:

A mole is defined as 6.022 × 10²³ of some chemical unit, be it atoms, molecules, ions, or others.

1 mole = 6.022 × 10²³ atoms

n(Ag) = 2.3 × 10²⁴ Ag atoms × (1 mol Ag/6.022 × 10²³ Ag atoms)

n(Ag) = 3.8193 mol Ag

Thus, the number of moles is 3.8193 moles.

Find more information about one mole here:

brainly.com/question/1358482

A hormone can have different effects in different species?
A. True
B. False
C. Cannot be decided

Answers

Answer:

true

Explanation:

it is because hormone determines various factors

Excess silver(I) nitrate was added to a 8.500 g mixture containing some amount of barium chloride, and 7.123 g of silver chloride was obtained. The unbalanced equation is
AgNO3 + BaCl2(aq) --> Ba(NO3)2(aq) + AgCl(s).
What is the mass% of BaCl2 in the mixture?

Answers

Answer:

60.88%

Explanation:

The balanced equation of the reaction is given as;

2 AgNO3 (aq) + BaCl2 (aq) → 2 AgCl (s) + Ba(NO3)2 (aq)

Since AgNO3 is in excess, the limiting reactant is BaCl2. From the reaction;

1 mol of BaCl2 produces 2 mol of AgCl

Converting to masses;

Mass = Number of mol * Molar mass

BaCl2;

Mass = 1 * 208.23 g/mol = 208.23 g

AgCl;

Mass = 2 * 143.32 g/mol = 286.64 g

208.23 g BaCl2 produces 286.64 g of AgCl

x g BaCl2 produces 7.123 g of AgCl

Solving for x;

x = 7.123 * 208.23 / 286.64 = 5.1745 g

Mass percent = Mass / Total mass of Mixture  * 100

Mass Percent = 5.1745 / 8.500 = 0.6088 * 100 = 60.88%

What mass of Iron (III) acetate will be produced when 1.50 grams of iron reacts in acetic acid?

Fe + H(C2H3O2) ® Fe(C2H3O2)3 + H2

Answers

Answer:

Fe + H(C2H3O2) ........

Both amines and amides are derivatives of
acetic acid
sodium hydroxide
ammonia
sodium chloride

Answers

Answer:

Ammonia

Explanation:

Both amines and amides are structurally similar to ammonia, the difference is the introduction of a carbon into the structure.

What is the main FUNCTION of the digestive system?
What are some of the main organs of the digestive system?

Answers

The main function of the digestive system is to break food down

Father, I come to you worn and weary from the hard times I have walked through recently. I come to you seeking your shelter where I know I can find security and rest in your shadow. Father, you are mighty. I know my circumstances are no match for Your great power. Father I place a healing of these people that they feel a conviction in there heart that they would turn from there wicked way and turn to you father. IN JESUS NAME AMEN

Answers

Answer:

Fact: There’s only one letter that doesn’t appear in any U.S. state name

And that is Q

Explanation:

Is snow organic or inorganic?

Answers

Answer:

snow is made up of a variety of mostly organic matter, including dead or dying animals and phytoplankton, protists, fecal matter, sand, and other inorganic dust.

Explanation:

I hope I helped!!

Plz mark me brainliest it would really make my day!

Answer:

I think its organic unless we are talking about this snow storm then no

What is the surface composition of planets in the solar system?

A,. Helium or hydrogen
B,. Rock or gas
C., Rock or water
D,. Water or helium

Answers

Answer:

B

Explanation:

Most planets in the solar system don't have water. Helium and hydrogen are two of the many gasses in planets. Therefore, B is the best answer.

3. A very large distillation column is separating p-xylene (more volatile) from o-xylene. The column has two feeds that are saturated liquids. Feed 1 flows into the column at a rate of 90 kmol/h and contains 42 mol% p-xylene. Feed 2 flows at a rate of 20 kmol/h and contains 9 mol% p-xylene. The bottoms product should be 97 mol% o-xylene, and the distillate product should be 99 mol% p-xylene. Compute the distillate (D) and the bottoms (B) products flow rates

Answers

Answer:

the distillate (D) and the bottoms (B) products flow rates are;

B = 72.1875 kmol/hr

D = 37.8125 kmol/hr

Explanation:

Given the data in the question;

as illustrated in the image below;

F1 stream, ( 90 kmol/hr ) contains 42 mol% p-xylene and Feed 2 ( 20 kmol/hr) contains 9mol% p-xylene, so;

more volatile → p-xylene

less volatile → o-xylene

now, Overall balance;

F1 + F2 = D + B

90 + 20 = D + B

D + B = 110    ------------- let this be equation 1

p-xylene. component balance;

0.42F1 + 0.09F2 = 0.99D +  0.03B

0.42(90) + 0.09(20) = 0.99D +  0.03B

37.8 + 1.8 = 0.99D +  0.03B

0.99D +  0.03B = 39.6 --------------- let this be equation 2

from equation 1 and 2

input (D = 110 - B) into equation 2

0.99(110 - B) +  0.03B = 39.6

108.9 - 0.99B + 0.03B = 39.6

108.9 - 39.6 = 0.99B - 0.03B

69.3 = 0.96B

B = 69.3 / 0.96

B = 72.1875

now, input B = 72.1875 into equation 1

D + B = 110

D + 72.1875 = 110

D = 110 - 72.1875

D = 37.8125

Therefore, the distillate (D) and the bottoms (B) products flow rates are;

B = 72.1875 kmol/hr

D = 37.8125 kmol/hr

La fórmula molecular del pentano y del nonano son​

Answers

Nose jajajajajaj si mr ayudas te ayudo

does a mole of hydrogen have the same mass as a mole of oxygen? explain your answer

Answers

Noah mall of hydrogen does not the see math as a more with oxygen because hydrogen is more strong and powerful than oxygen oxygen can increase the rating of the volume

You dissolve 0.64 g of potassium chloride (KCl) in 725 ml of water.
What is the molarity of the solution?
(From the periodic table: 1 mol K = 39.10 g; 1 mol Cl = 35.453 g)
Enter the value rounded to three decimal places with no units
Will give BRAINLEST

Answers

Answer:

0.012 M

Explanation:

Step 1: Given and required data

Mass of KCl (m): 0.64 gVolume of water (V): 725 mL (We will assume it is equal to the volume of the solution)Molar mass of KCl (M): 74.553 g/mol

Step 2: Calculate the moles (n) of solute (KCl)

We will use the following expression.

n = m/M = 0.64 g / (74.553 g/mol) = 8.6 × 10⁻³ mol

Step 3: Calculate the molar concentration (C) of the solution

The molarity is equal to the moles of solute divided by the liters of solution.

C = 8.6 × 10⁻³ mol/0.725 L = 0.012 M

Which of the following is evidence that a chemical
change is occurring?

a. Cherry drink mix is added to water and the resulting
solution is red.

b. A white powder is added to cool tap water in a beaker
and the beaker gets hot.

c. Water is added to coffee until the solution becomes
clear.

d. Water is added to sand and the sand looks darker

Answers

Answer:

c. water is added to coffe until the solution becomes clear

Answer:

c

Explanation:

Water is added to coffee until the solution becomes

clear.

3. Una piedra que se tira verticalmente hacia arriba se mueve según la

leys = 64y - 8t^2, si "s" se mide en pies (ft) y t en segundos, hallar:

a) SU posición y velocidad después de dos segundos y después de tres

segundos.

b) ¿Qué altura alcanzará?

c) ¿A qué distancia se moverá al cabo del cuarto segundo?

Answers

Answer:

Explanation:

Para mejor entendimiento, reeescribiremos la ley que pusiste:

S = 64t - 8t²    (1)

De acuerdo al enunciado del problema, S tiene unidades de pie y t en segundos, por lo tanto, S, que se refiere a la posición o altura alcanza de la piedra, puede ser determinado usando esa expresión a tiempos específicos.

Para el calculo de velocidad usamos la siguiente expresión:

V = -g * t     (2)      g: 32.16 ft/s

Tomando en cuenta estas expresiones, veamos los valores de posición y velocidad:

a) Para t = 2 s

S = 64(2) - 8(2)²

S = 96 ft

V = -32.16 * 2

V = -64.32 ft/s

Para t = 3 s

S = 64(3) - 8(3)²

S = 120 ft

V = -32.16 * 3

V = -96.48 ft/s

b) Para saber la altura que alcanzará, usamos la expresión de altura máxima que es la siguiente:

Smáx = -V₀² / 2g   (3)

Para el valor de la velocidad inicial, podemos asumir el valor de la velocidad dada por la formula de la ley S, que es 64. Esto porque al ser multiplicado por el valor del tiempo, queda en unidades de distancia, asi que este valor debe tener unidades de velocidad. Reemplazando este valor en la expresión:

Smáx = -(64)² / 2 * 32.16

Smáx = 63.68 ft

c) Para esta parte, usamos nuevamente la formula de la ley S, usando t = 4 s y listo:

S = 64(4) - 8(16)

S = 128 ft

Espero te sirva

What is the surface composition of planets in the solar system?

A,. Helium or hydrogen
B,. Rock or gas
C., Rock or water
D,. Water or helium

Answers

Answer:

A: Helium or Hydrogen

Explanation:

Terrestrial planets are the 4 inner most planets of the solar system which are mercury, venus, earth, Mars, while the giant planets are the 4 outer most which are Jupiter, Saturn, Uranus and Neptune.

Now, these outer most ones are the surface ones and are surrounded primarily by layers of hydrogen and helium gases.

which explains how coolers work?

Answers

Answer:

Forgive me if im wrong but i am pretty sure the answer is C

Explanation:

How many CaF are in a 1.7x10^25 please I need help fast!!

Answers

Answer:

28 mol CaF

General Formulas and Concepts:

Math

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Chemistry

Atomic Structure

Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Stoichiometry

Using Dimensional AnalysisExplanation:

Step 1: Define

[Given] 1.7 × 10²⁵ molecules CaF

[Solve] moles CaF

Step 2: Identify Conversions

Avogadro's Number

Step 3: Convert

[DA] Set up:                                                                                                          [tex]\displaystyle 1.7 \cdot 10^{25} \ molecules \ CaF(\frac{1 \ mol \ CaF}{6.022 \cdot 10^{23} \ molecules \ CaF})[/tex][DA] Multiply/Divide [Cancel out units]:                                                         [tex]\displaystyle 28.2298 \ moles \ CaF[/tex]

Step 4: Check

Follow sig fig rules and round. We are given 2 sig figs.

28.2298 mol CaF ≈ 28 mol CaF

Which of the following destroys the marine ecosystem?
A. fishpond C. dynamite fishing
B. reclamation D. constructing man-made sanctuaries​

Answers

C. Dynamite fishing

dynamite fishing is a destructive fishing practice using explosives to stun or kill schools of fish for easy collection. This often illegal practice is extremely destructive to the surrounding ecosystem, as the explosion often destroys the underlying habitat that supports the fish.

Answer:

The correct one is dynamite fishing

In the lab activity, the reaction rate was determined by the appearance of a product. However, the reaction rate can also be determined by the disappearance of a reactant. Rate =Δ[product]/Δt or rate−Δ[reactant]Δt. In each situation below, you are given a rate measured by the appearance of one component of the reaction and are asked to predict the rate of appearance or disappearance of another component, based on logic and stoichiometric relationships.

For example, if the reaction is as follows:

A+2B⟶products

For every mole of A that is used, 2 moles of B are used so the rate of disappearance of B is twice the rate of the disappearance of A.

This may be expressed as:

rate=−Δ[B]/Δt=−2[A]/Δt , N2(g)+3H2(g)⟶2NH3(g)

The reaction rate is measured as 0.032 M NH3/s. Determine the rate of disappearance of N2 and the rate of disappearance of H2. Explain how you arrived at your answers.

Answers

Answer: Rate of disappearance of [tex]N_2[/tex]= 0.032 M/s

Rate of disappearance of [tex]H_2[/tex] = 0.096 M/s

Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

[tex]N_2(g)+3H_2(g)\rightarrow 2NH_3(g)[/tex]

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.

Rate in terms of disappearance of [tex]N_2[/tex] = [tex]-\frac{1d[N_2]}{dt}[/tex]

Rate in terms of disappearance of [tex]H_2[/tex] = [tex]-\frac{1d[H_2]}{3dt}[/tex]

Rate in terms of appearance of [tex]NH_3[/tex] = [tex]\frac{1d[NH_3]}{2dt}[/tex]

Rate = [tex]-\frac{1d[N_2]}{dt}=-\frac{1d[H_2]}{3dt}=\frac{1d[NH_3]}{2dt}[/tex]

Given : = 0.032 M/s

Rate of disappearance of =

Rate of disappearance of [tex]H_2[/tex] = [tex]-\frac{d[H_2]}{dt}=3\times 0.032M/s=0.096M/s[/tex]

I need help plz quick on my homework its due at 11 i will give branliest to correct answer its on limiting reagents.

Answers

Answer:4.2 6.4 6.7 9.5 5.5 3.8

Explanation:

DNA forms two strands. One of the strands of a piece of a DNA molecule has the bases ATA.

Which bases does the other strand have?
Select one:

A: CAC.

B: TAT.

C: GTG.

D: ATA.

Answers

Answer:

b

Explanation:

Combinations between two strands:

T - A

A - T

C - G

G - C

(so if one strand has A for example, then the other strand must have T in the same spot)

Bases   which are present on the other strand of DNA are TAT.

What is DNA?

DNA or deoxyribonucleic acid is a hereditary material present in humans as well as all living beings. Almost every cell present in the body has DNA. Most DNA are located inside the cell , that is in the nucleus of the cell. But a small portion of DNA  can be found in the mitochondria of the cell as well.

The information in DNA is stored as a code which is composed of four chemical bases 1) adenine 2)guanine 3) cytosine  4) thymine . The human DNA consists of 3 billion bases . The order of of these bases determine information which is used for building and maintaining an organism.

The DNA bases can pair with each other .Adenine pairs with thymine   and guanine with cytosine to form units which are called as base pairs.Each base apart from other complementary base it also attaches itself to a sugar and a phosphate molecule.

Learn more about DNA ,here:

https://brainly.com/question/22499464

#SPJ6

At room temperature, CsF is expected to be:______.
a. a soft solid.
b. a conducting solid.
c. a gas.
d. a brittle solid.
e. a liquid.

Answers

Answer:

d. a brittle solid.

Explanation:

Hello!

In this case, since cesium fluoride is widely known as an ionic compound due to the large electronegativity difference, it is possible to discard a. due to its crystalline structure, b. because conducting solids are metals, c. because ionic compounds are not likely to be gases and e. because even when it is soluble in water, the problem is not referring to an aqueous solution; therefore, the answer is d. a brittle solid.

Best regards!

when an object kinetic energy changes what happens to the object??

Answers

Answer:

2. A 3.C

Explanation:

When a chemical reaction is run in aqueous solution inside a calorimeter, the temperature change of the water (and Ccal) can be used to calculate the enthalpy change for the reaction. Here, we will study the reaction of hydrochloric acid with sodium hydroxide in the calorimeter from problem 3. Equal volumes (50.0 mL) of 1.00 M sodium hydroxide and 1.00 M hydrochloric acid are mixed.
HCl+NaOH→NaCl+H2O
1. What is the total change in enthalpy (in Joules) for the reaction?
2. Where initial temperature is 21.2 °C and final temperature is 28.0 °C. Ccal is 1234.28 j

Answers

Answer:

The total change in enthalpy for the reaction is - 81533.6 J/mol

Explanation:

Given the data in the question;

Reaction;

HCl + NaOH → NaCl + H₂O

Where initial temperature is 21.2 °C and final temperature is 28.0 °C. Ccal is 1234.28 J

Moles of NaOH  = 50.mL × 1.00 M = 50.0 mmol = 0.0500 mol

Moles of HCl = 50.mL × 1.00 M = 50.0 mmol = 0.0500 mol

so, 0.0500 moles of H₂O produced

Volume of solution = 50.mL  +  50.mL  = 100.0 mL

Mass of solution m = volume × density = 100.0mL × 1.0 g/mL = 100 g

now ,

Heat energy of Solution q= (mass × specific heat capacity × temp Δ) + Cal

we know that; The specific heat of water(H₂O) is 4.18 J/g°C.

so we substitute

q_soln = (100g × 4.18 × ( 28.0 °C - 21.2 °C) ) + 1234.28

q_soln = 2842.4 + 1234.28

q_soln = 4076.68 J

Enthalpy change for the neutralization is ΔH[tex]_{neutralization}[/tex]

ΔH[tex]_{neutralization}[/tex] = -q_soln / mole of water produced

so we substitute

ΔH[tex]_{neutralization}[/tex] = -( 4076.68 J ) / 0.0500 mol  

ΔH[tex]_{neutralization}[/tex] = - 81533.6 J/mol

Therefore, the total change in enthalpy for the reaction is - 81533.6 J/mol

In a technique used for surface analysis called auger electron spectroscopy (AES), electrons are accelerated toward a metal surface. These electrons cause the emissions of secondary electrons (called auger electrons) from the metal surface. The kinetic energy of the auger electrons depends on the composition of the surface. The presence of oxygen atoms on the surface results in auger electrons with a kinetic energy of approximately 520 eV .

Required:
What is the de Broglie wavelength of one of these electrons?

Answers

Answer:

the de Broglie wavelength of one of the electrons is 5.3787 × 10⁻¹¹ m

Explanation:

Given the data in the question;

we know that; ( electron volt ) 1 eV = 1.602 × 10⁻¹⁹ J

so given that Kinetic Energy KE = 520 eV

KE = 520 × 1.602 × 10⁻¹⁹ = 8.3304 × 10⁻¹⁷ J

we know that;

Kinetic Energy = 1/2 × mv²

where m is the electron mass

and mass of electron is  9.109 × 10⁻³¹ kilograms

so

8.3304 × 10⁻¹⁷ = 1/2 × 9.109 × 10⁻¹⁷× v²

v = √[(8.3304 × 10⁻¹⁷) / (1/2 × 9.109 × 10⁻³¹)]

v = 1.3524 × 10⁷ m/s

speed of the electron v = 1.3524 × 10⁷ m/s

now, de Broglie equation;

wavelength λ = h / mv

where h is Planck constant ( 6.626 × 10⁻³⁴ m² kg / s )

so we substitute

wavelength λ = 6.626 × 10⁻³⁴ / ( 9.109 × 10⁻³¹ × 1.3524 × 10⁷)

wavelength λ = 5.3787 × 10⁻¹¹ m

Therefore, the de Broglie wavelength of one of the electrons is 5.3787 × 10⁻¹¹ m

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Can Someone Please!! Help me A seed of a plant sticks to the fur of an animal as it walks by.How has the animal most likely helped the plant? Jeni walks 100 meters east and then 50 meters north. How big is Jeni's displacement from the starting point? a. 100 meters b. 150 metersc. 50 meters d. About 112 meters Lines 1-19: What does Wiesel do to get listeners' attention at the beginning of hisspeech? Why might Wiesel have chosen to begin this way? For the base b of a logarithmic function, b>0 and b1TrueFalse Explain the difference between a sell-by date and a use-by date. Which of the following pieces of information from the selection from Life on the Mississippi is presented in the form of an anecdote? A. the author's inclusion of technical words used by the apprentice engineer B. the author's account of his first attempt to get a job on a steamboat C. the author's long description of the decorations on the packet boat D. the author's description of the residents of his hometown ANSWER THIS QUESTION PLZZZ HELP ME PLEASE Name two systems and for each one list two social factors that have caused those systems to evolve. Discuss your answers with a partner. 5x-45x (Factor COMPLETELY) Dominic notices That his pool loses a little water each day and needs to be re-filled often in the hot Texas summer. What is the most likely cause? Here is the graph for one equation in a system of equations:a. Write a second equation for the system so it has infinitely many solutions.b. Write a second equation whose graph goes through (0,1) so the system has no solutionsc. Write a second equation whose graph goes through (0,2) so the system has one solution at (4,1) What is the main purpose of a local planning and zoning department? A. to maintain parks and recreational facilitiesB. to decide on the location of new neighborhoodsC. to build sufficient affordable housingD. to maintain roads and transportation systems Alida dropped her wallet and lost her credit card while boarding a train. She informed the credit card company immediately to prevent misuse of her lost card However, later the same day. Alicia received a message from the card company that purchases worth $900 had been made using her credit card How much is Alicia responsible for paying? Select the correct answer from each drop-down menu. According to the (A. Fair Credit Billing, B. Fair Credit Reporting, C. Truth in tending Act), Alida is responsible for paying (A. $0, B. $50, C. $900), because she reported the lost card before it was used. DESPERATE WILL GIVE BRAINLIST AND THANKSHow many men and women were a part of the military in 1941?8800,0008 Million1,600,000 In the end of the play A Raisin in the Sunthe youngers decide to move to the new neighborhood in spite of the racism they encounter. Why did they decide to make that decision and what are the risks and rewards of deciding to do so? NEEDS TO BE 5-7 SENTENCES If f(x) = -(5)x , what is f(2)? Ill give brainly please help (7th grade history) How did World War I finally end? what is 15% of 80????