what is the molar masses for C8H10N2O4

Answers

Answer 1

Answer:

198.2 g/mol

Explanation:

C = 12.01 g/mol

H = 1.01 g/mol

N = 14.01 g/mol

O = 16.00 g/mol

(12.01 x 8) + (10 x 1.01) + (14.01 x 2) + (16.00 x 4) = 198.12 g/mol


Related Questions

For the following reaction, 11.6 grams of sulfur are allowed to react with 23.8 grams of carbon monoxide .

sulfur(s) + carbon monoxide(g) sulfur dioxide(g) + carbon(s)

What is the maximum amount of sulfur dioxide that can be formed?

What is the formula for the limiting reagent?

What amount of the excess reagent remains after the reaction is complete?

Answers

Answer:

S + 2CO = SO2 + 2C

First, look for the amount of substance of sulfur:

n(S) = m / M

n(S) = 14.8 g/32 g / mol = 0.4625 mol

n(CO) = m (CO) / M (CO)

M(CO) = 12 + 16 = 28 g/mol

n(CO) = 19.9 g/28 g/mol = 0.71 mol

S in excess, so for calculating we take CO:

n(SO2) = n(CO)/2 = 0.71 mol/2 = 0.355 mol

m(SO2) = M(SO2)*n(SO2)

M(SO2) = 32 + 16*2 = 64 g/mol

m(SO2) = 64 g/mol * 0.355 mol = 22.74 g

How much would the freezing point of water decrease if 4 mol of sugar were added to 1kg of water?

Answers

Answer:

7.44 C is the answer of the question.

Explanation:

Combustion of 29.26 gg of a compound containing only carbon, hydrogen, and oxygen produces 33.86 gCO2gCO2 and 13.86 gH2OgH2O. Part A What is the empirical formula of the compound

Answers

Answer:

C2H4O3

Explanation:

Empirical formula is defined as the simplest whole number ratio of atoms present in a molecule.

To solve this question we need to find the moles of carbon = Moles of CO2, the moles of hydrogen (Using moles of H2O) and the moles of oxygen (Finding the mass of the mass of each atom) as follows:

Moles Carbon -Molar mass CO2: 44.01g/mol-:

33.86g CO2 * (1mol/44.01g) = 0.769 moles CO2 = Moles C * (12g/mol) =

9.23g C

Moles Hydrogen -Molar mass H2O: 18.01g/mol-

13.86g H2O * (1mol/18.01g) = 0.770 moles H2O * (2mol H / 1mol H2O) = 1.54 moles H * (1g/mol) = 1.54g H

Moles Oxygen:

Mass: 29.26g - 9.23g C - 1.54g H = 18.49g O * (1mol/16g) = 1.156 moles O

Dividing each number of moles in the moles of C (Lowe number of moles):

C = 0.769 moles C / 0.769 moles C  = 1

H = 1.54 moles H / 0.769 moles C = 2

O = 1.156 moles O / 0.769 moles C = 1.5

As the number must be a whole number each ratio twice:

C = 2

H = 4

O = 3

Empirical formula is:

C2H4O3

3. The electrolyais of water produces oxygen gas at the rate of 32.5 mL/min in a certain experiment.
What volume of oxygen gas can be produced in 7.50 min?

Answers

Answer:

243.75 mL

Explanation:

In 1min 32.5 mL of oxygen

In 7.5 min electrolysis of water produces

(32.5mL × 7.5 min)/ 1min

= 243.75mL

what the movement of the earth around the sun​

Answers

Answer:

Yan po Ang sagot NASA pic

Explanation:

pa heart po plss

at pa vote

CORRECT ME IF IM WRONG

FOLLOW ME AND I FOLLOW BACK YOU☺️☺️☺️♥️♥️

Answer:

The movement of the earth around the sun in a fixed path or orbit is called Revolution. The axis of the earth which is an imaginary line, makes an angle of 66½° with its orbital plane. ... The earth takes about 24 hours to complete one rotation around its axis.

What would you expect to observe when Br2 reacts with 2-butyne?

Answers

Answer:

I expect to observe a change in colour from reddish brown to a colourless solution

Explanation:

Bromine (Br2) attacks the electron rich carbon-carbon triple bond in but-2-yne, an alkyne to form an initial product 2, 3 dibromobut-2-ene; which reacts with excess bromine to form a final product 2,2,3,3 -tetrabromobutane.

The reaction occurs in two steps. On approaching but-2-yne, bromine molecule becomes polarised forming an induced dipole containing a bromonium ion.

Br - Br → Br+ - Br-

The bromonium ion (Br+) formed then attacks the carbon - carbon triple bond to form the initial product

2,3- dibromobut-2-ene

CH2-C≡C-CH2 + Br+ →

CH2 - CBr =CBr-CH2

(2,3- dibromobut-2-ene)

Which in the presence of excess bromine gives the final product

2,2,3,3 - tetrabromobutane.

CH2 - CBr =CBr-CH2 + Br2 →

CH3 -CBr2-CBr2 - CH3

2,2,3,3 - tetrabromobutane.

A visible change in colour from the reddish-brown colour of Bromine to a colourless solution is observed during the reaction.

I have an unknown volume of gas held at a temperature of 115 K in a container with a pressure of 60atm. If by increasing the temperature to 225 K and decreasing the pressure to 30. atm causes the volume of the gas to be 29 liters, how many liters of gas did I start with?
SHOW YOUR WORK

Answers

Explanation:

here is the answer to your question.

Copper reacts with sulfuric acid to yield copper(II) sulfate, water, and sulfur dioxide.

a. True
b. False

Answers

Answer:

B. False

Explanation:

Water does NOT react too copper. Copper does not react with water because the oxygen in water is locked into a compound with one part oxygen and two parts hydrogen. Copper oxide is a compound from the two elements copper and oxygen. Everything else listed does but since water is on this list it is false.

Many chemistry problems result in equations of the form
1.77 X100.298-z)
When this equation is solved, the two values of the unknown are ________ and ________

Answers

Answer:

When this equation is solved, the two values of the unknown are 0.0643 and -0.082

Explanation:

Given

[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex] --- the actual equation

Required

The values of x

We have:

[tex]1.77 * 10^{-2} = \frac{x^2}{0.298 - x}[/tex]

Cross Multiply

[tex]1.77 * 10^{-2} * (0.298 - x)= x^2[/tex]

Multiply both sides by 100

[tex]1.77 * (0.298 - x)= 100x^2[/tex]

Open bracket

[tex]0.52746 - 1.77x= 100x^2[/tex]

Rewrite as:

[tex]100x^2 + 1.77x - 0.52746 =0[/tex]

Using quadratic formula:

[tex]x = \frac{-b \± \sqrt{b^2 - 4ac}}{2a}[/tex]

Where:

[tex]a = 100; b = 1.77; c = -0.52746[/tex]

So, we have:

[tex]x = \frac{-1.77 \± \sqrt{1.77^2 - 4*100*- 0.52746 }}{2*100}[/tex]

[tex]x = \frac{-1.77 \± \sqrt{214.1169}}{2*100}[/tex]

[tex]x = \frac{-1.77 \± 14.63}{200}[/tex]

Split

[tex]x = \frac{-1.77 + 14.63}{200}\ or\ x = \frac{-1.77 - 14.63}{200}[/tex]

[tex]x = \frac{12.86}{200}\ or\ x = \frac{-16.40}{200}[/tex]

[tex]x = 0.0643\ or\ x = -0.082[/tex]

A chemist determines by measurements that 0.0800 moles of bromine liquid participate in a chemical reaction. Calculate the mass of bromine liquid that participates. Round your answer to 3 significant digits.

Answers

Answer:

The mass of bromine liquid that participates in  a chemical reaction=12.8 g

Explanation:

We are given that

Total number of moles of bromine liquid participate in chemical reaction=0.0800 moles

We have to find the mass of bromine liquid that participates.

Atomic mass of Br=79.9 g

1  mole of bromine liquid=2 atomic mass of bromine (Br)

1 mole of bromine liquid ([tex]Br_2[/tex]) =[tex]2\times 79.9=159.8 g[/tex]

0.0800 moles of  bromine liquid=[tex]159.8\times 0.0800[/tex] g

0.0800 moles of  bromine liquid=12.784 g

0.0800 moles of  bromine liquid[tex]\approx 12.8[/tex] g

Hence, the mass of bromine liquid that participates in  a chemical reaction=12.8 g

g n the following three compounds(1,2,3) arrange their relative reactivity towards the reagent CH3Cl / AlCl3. Justify your order

Answers

Answer:

3 > 2> 1

Explanation:

Aromatic compounds undergo electrophilic substitution reaction which passes through a positively charged intermediate to yield the product.

Substituted benzenes may be more or less reactive towards electrophilic aromatic substitution than benzene molecule depending on the nature of the substituent.

Certain substituents increase the ease of reaction of benzene towards aromatic substitution.

If we look at the compounds closely, we will notice that toluene reacts readily with CH3Cl / AlCl3. This is because, the methyl group is electron donating hence it stabilizes the positively charged intermediate produced in the reaction.

Carbonyl compounds are electron withdrawing substituents hence they decrease the magnitude of the positive charge and hence decrease the rate of electrophilic aromatic substitution.

A major component of gasoline is octane when octane is burned in air it chemically reacts with oxygen to produce carbon dioxide and water what mass of carbon dioxide is produced by the reaction of oxygen

Answers

gasoline is the chemical that is coming out of the air

Part A: Calculate the mass of butane needed to produce 75.6g of carbon dioxide.

Part B: Calculate the mass of water produced when 5.48g of butane reacts with excess oxygen.

Answers

Answer:

Multiply the number of moles of butane by its molar mass, 58.12g/mol, to produce the mass of butane. Mass of butane = 18.8g.

Explanation:

Part B:

The mass of water produced when 4.86 g of butane(C4H10) react with excess oxygen is calculated as below

calculate the moles of C4H10 used = mass/molar mass

moles = 4.86g/58 g/mol =0.0838 moles

write a balanced equation for reaction

2 C4H10 + 13 O2 = 8 CO2 + 10 H2O

by use of mole ratio between C4H10 to H2O which is 2:10 the moles of

H20= 0.0838 x10/2 = 0.419 moles of H2O

mass = moles x molar mass

=0.419 molx 18 g/mol = 7.542 grams of water is formed

(URGENT!) Which of these graphs best models the waves in the four locations?
(100 points)

Answers

i can not understand the question. There seems to be missing info

mass of exactly 1 mole of arsenic

Answers

Answer:

The average mass of one atom of arsenic is 74.92 amu, and the mass of one mole of arsenic atoms is 74.92 grams.

The mass of one mole of arsenic atoms is 74.92 grams.

Calculation,

Mass of one mole of arsenic = Mass of 1 arsenic atom × [tex]N_{A}[/tex]

Where, [tex]N_{A}[/tex] = Avogadro's number = 6.022 × [tex]10^{23}[/tex]

Mass of one arsenic atom = 74.921 u

One u =  1.66 × [tex]10^{-27}[/tex] kg

And,

Mass of one mole of arsenic atom = 6.022 ×[tex]10^{23}[/tex] × 74.921 × 1.66 × [tex]10^{-27}[/tex]×[tex]10^{3}[/tex] kg

Mass of one mole of arsenic atom = 74.92 [tex]gmol^{-1}[/tex]

What is molar mass?The mass of one mole of a substance in grams is called molar mass.The unit is [tex]gmol^{-1}[/tex].

To learn more about molar mass,

https://brainly.com/question/12127540

#SPJ2

Calculate the vapor pressure (in torr) at 298 K in a solution prepared by dissolving 46.8 g of the non-volatile non-electrolye glucose in 117 g of methanol. The vapor pressure of methanol at 298 K is 122.7 torr. Enter your answer to 2 decimal places.

Answers

Answer: The total partial pressure of the solution is 131.37 torr.

Explanation:

The number of moles is defined as the ratio of the mass of a substance to its molar mass. The equation used is:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex] ......(1)

For glucose:

Given mass of glucose = 46.8 g

Molar mass of glucose = 180 g/mol

Plugging values in equation 1:

[tex]\text{Moles of glucose}=\frac{46.8g}{180g/mol}=0.26 mol[/tex]

For methanol:

Given mass of methanol = 117 g

Molar mass of methanol = 32 g/mol

Plugging values in equation 1:

[tex]\text{Moles of methanol}=\frac{117g}{32g/mol}=3.66 mol[/tex]

Mole fraction is defined as the moles of a component present in the total moles of a solution. It is given by the equation:

[tex]\chi_A=\frac{n_A}{n_A+n_B}[/tex] .....(2)

where n is the number of moles

Putting values in equation 2:

[tex]\chi_{methanol}=\frac{3.66}{0.26+3.66}=0.934[/tex]

Raoult's law is the law used to calculate the partial pressure of the individual gases present in the mixture. The equation for Raoult's law follows:

[tex]p_A=\chi_A\times p_T[/tex] .....(3)

where [tex]p_A[/tex] is the partial pressure of component A in the mixture and [tex]p_T[/tex] is the total partial pressure of the mixture

We are given:

[tex]p_{methanol}=122.7torr\\\chi_{methanol}=0.934[/tex]

Putting values in equation 3, we get:

[tex]122.7torr=0.066\times p_T\\\\p_T=\frac{122.7torr}{0.934}=131.37torr[/tex]

Hence, the total partial pressure of the solution is 131.37 torr.

Question 2 Classify the following statement as a prediction, observation, theory, or law. Please be sure to classify the statement exactly as it is written! A helium filled balloon floats.

Answers

Answer:

Theory

Explanation:

We are given the statement;

"A helium filled balloon floats."

Now, this statement is an attempt to explain to us why balloons float. And the reason is because they are filled with helium. This is no prediction or law or observation because to find out if the balloons contain helium, there must have been experiments to confirm that.

Thus, the statement in the question is a theory.

What mass of steam initially at 120oC is needed to warm 200g of water in a glass container from 20.0 oC to 50.0 oC

Answers

Complete question:

What mass of steam initially at 120 ⁰C is needed to warm 200g of water in a 100 g glass container from 20.0 oC to 50.0 ⁰C

Answer:

the initial mass of the steam is 10.82 g

Explanation:

Given;

mass of water, m₁ = 200 g

mass of the glass, m₂ = 100 g

temperature of the steam = 120 ⁰C

initial temperature of the water, 20⁰ C

final temperature of the water, = 50⁰ C

let the mass of the steam = m

specific heat capacity of water c = 1 cal/g ⁰ C

specific heat capacity of glass c₂ = 0.2 cal/g ⁰ C

laten heat of vaporization of steam L = 540 cal/g

Apply principle of conservation energy;

Heat given off by the steam = Heat absorbed by water + heat absorbed by glass

[tex]mc\Delta T_1 + mL + mc\Delta T_2 = m_1c\Delta T_3 + m_2c_2\Delta T_3\\\\mc\Delta T_1 + mL + mc\Delta T_2 = [m_1c + m_2c_2]\Delta T_3[/tex]

m(1) (120 - 100)  +  m(540)  + m(1) (100 - 50) = [200(1)  +  100(0.2)] (50 - 20)

20m + 540m + 50m = 6600

610 m = 6600

m = 6600 / 610

m = 10.82 g

Therefore, the initial mass of the steam is 10.82 g

The first law of thermodynamics defines chemical energy. defines entropy. is a statement of conservation of energy. provides a criterion for the spontaneity of a reaction.

Answers

Answer: The first law of thermodynamics is a statement of conservation of energy.

Explanation:

According to the first law of thermodynamics, heat provided to a system is actually the sum of internal energy and work done by the system or on the system.

Mathematically, [tex]\Delta Q = \Delta U + \Delta W[/tex]

The first law of thermodynamics also means that energy can neither be created nor it can be destroyed. Hence, energy is conserved.

Thus, we can conclude that the first law of thermodynamics is a statement of conservation of energy.

Calculate the mass of butane needed to produce 80.0g of carbon dioxide

Answers

Answer:

Multiply the number of moles of butane by its molar mass, 58.12g/mol, to produce the mass of butane. Mass of butane = 18.8g.

the Wavelength of a microwave is______than the wavelength of visible light
(Please help)

Answers

Answer:

The wavelength of a microwave is LONGER than the wavelength if visible light.

Write the number of sig. fig. in four numbers given in the sentence below. An (one) octopus has 8 legs. 13 octopi have 104 legs.
Give four answers.
A. Infinity, Infinity, Infinity, Infinity
B. 1, 1, 2, 3
C. Infinity, Infinity, 2, 3
D. No answer text provided.​

Answers

Answer:

1, 1, 2, 3

Explanation:

The numbers 1 and 8 both have 1 sig. fig.

The number 13 has 2 sig. figs.

The number 104 has 3 sig. figs.

How many protons are in Oxygen-18 and how many neutrons are in Copper-65? Please include steps for solving both!

Answers

Answer: There are 8 protons in oxygen-18 and 36 neutrons in copper-65.

Explanation:

An atom contains three sub-atomic particles, that is, protons, neutrons and electrons.

The atomic number is the total number of protons present in an atom. For oxygen-18, the atomic mass is 18.

Atomic mass is the sum of total number of protons and electrons present in an atom. As the atomic number of an oxygen atom is 8 so the number of protons present in oxygen-18 is 8.

The atomic mass of copper is 65 and for a copper atom, the atomic number is 29. Hence, the number of neutrons for copper-65 is as follows.

Atomic mass = no. of protons + no. of neutrons

65 = 29 + no. of neutrons

no. of neutrons = 65 - 29 = 36

Thus, we can conclude that there are 8 protons in oxygen-18 and 36 neutrons in copper-65.

In a classroom, students who are biochemistry majors are learning about the overall organization of biological membranes. However, one of the students finds a WRONG explanation about the fluid mosaic model from a website and bring it up in a discussion. Which of the following is a WRONG explanation?

a. An explanation of the two-dimensional solutions of oriented lipids and globular proteins.
b. The lipid bilayer is a solvent for integral membrane proteins.
c. All membrane proteins diffuse laterally and freely in the lipid matrix.
d. None of the answers is correct.
e. The lipid bilayer is a permeability barrier for integral membrane proteins.

Answers

Answer:

e. The lipid bilayer is a permeability barrier for integral membrane proteins.

Explanation:

Integral membrane proteins enter the lipid bilayer by translocon channel which gives nascent polypeptide segment a chance to partition itself into lipid bilayer hydrophobic core.

Please help me ASAP in my final project I am ready to pay 20$

Answers

Answer:

$20

ASAP PROJECT

Determine the kinds of intermolecular forces that are present in each element or compound. Part A KrKr Check all that apply. Check all that apply. dispersion forces dipole-dipole forces hydrogen bonding

Answers

Answer:

The kinds of intermolecular forces that are present in each element Kr-Kr.

Explanation:

Since Kr is an inert gas and in atomic form only it is highly stable.

So, Kr gas does not form molecules.

Between the atoms of inert gas, there exist London dispersion forces.

Hence, the intermolecular forces that are present between Kr-Kr atoms is London dispersion forces.

list four energy resources​

Answers

Answer:

Nuclear

Solar

Wind

Hydro

Geo-Thermal

Explanation:

Solar energy from the sun.Geothermal energy from heat inside the earth.Wind energyBiomass from plants.

hope it helps

stay safe healthy and happy....


The speed of light_____ meters per second

Answers

299,792,458 meters per second.

a compound has a percent compostion of carbon equal to 48.8383%, hydrogen equal to 8.1636%, and oxygen equal to 43.1981%. what is the mepirical formula

Answers

Answer:

C₂H₃O

Explanation:

From the question given above, the following data were obtained:

Carbon (C) = 48.8383%

Hydrogen (H) = 8.1636%

Oxygen (O) = 43.1981%

Empirical formula =?

The empirical formula of the compound can be obtained as follow:

C = 48.8383%

H = 8.1636%

O = 43.1981%

Divide by their molar mass

C = 48.8383 / 12 = 4.07

H = 8.1636 / 1 = 8.1636

O = 43.1981 / 16 = 2.7

Divide by the smallest

C = 4.07 / 2.7 = 2

H = 8.1636 / 2.7 = 3

O = 2.7 /2.7 = 1

Thus, the empirical formula of the compound is C₂H₃O

The following physical constants are for water, H2O.
The specific heat capacity of the solid = 2.09 J/g oC
The specific heat capacity of the liquid = 4.18 J/g oC
The specific heat capacity of the vapor = 2.09 J/g oC
∆Hfus = 6.02 kJ/mol; ∆Hvap = 40.7 kJ/mol Freezing point = 0.0oC; Boiling point = 100.0oC
How much heat(in kJ) is required to warm 10.0 grams of ice at -5.0oC to a temperature of 70.0oC?

Answers

Answer:

[tex]Q\approx6.4~kJ[/tex]

Explanation:

Quantity of heat required by 10 gram of ice initially warm it from -5°C to 0°C:

[tex]Q_1=m.C_s.\Delta T[/tex]

here;

mass, m = 10 g

specific heat capacity of ice, [tex]C_s=2.09~J.g^{-1}.^{\circ}C^{-1}[/tex]

change in temperature, [tex]\Delta T=(5-0)=5^{o}C[/tex]

[tex]Q_1=10\times2.09\times 5[/tex]

[tex]Q_1=104.5~J[/tex]

Amount of heat required to melt the ice at 0°C:

[tex]Q_2=m.\Delta H_{fus}[/tex]

where, [tex]\Delta H_{fus}=6020~J/mol[/tex]

we know that no. of moles is = (wt. in gram) [tex]\div[/tex] (molecular mass)

[tex]Q_2=\frac{10}{18} \times 6020[/tex]

[tex]Q_2=3344.44~J[/tex]

Now, the heat required to bring the water to 70°C from 0°C:

[tex]Q_3=m.C_L.\Delta T[/tex]

specific heat of water, [tex]C_L=4.18~J/g/^oC[/tex]

change in temperature, [tex]\Delta T=(70-0)=70^oC[/tex]

[tex]Q_3=10\times 4.18\times 70[/tex]

[tex]Q_3=2926~J[/tex]

Therefore the total heat required to warm 10.0 grams of ice at -5.0°C to a temperature of 70.0°C:

[tex]Q=Q_1+Q_2+Q_3[/tex]

[tex]Q=104.5+3344.44+2926[/tex]

[tex]Q=6374.94~J[/tex]

[tex]Q\approx6.4~kJ[/tex]

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Mr. Hamilton decorates his U.S. History classroom by putting up pictures of the presidents. The wall is 9.75 feet long. In the center, there is a window that is 5 feet long.Each president's picture is 6 inches wide.4. How would your answer change if the pictures were 10 inches wide? Explain. Write Short Note On:Happiness as the indicator development 22. The ratio in which (4, 5) divides the join of (2, 3)and (7, 8) is :(a) 4 : 3(c) 3 : 2(b) 5:2(d) 2:3 lee is planning an event for 28 people, he wants to make a fruit drink and he thinks that each person will drink 3 glasses each. If he is correct , how many glasses of fruit should he make? It is back-to-school time in much of the world. Calm, easy mornings are replaced withbusy, hurried ones. Children wake up early and get ready for school. Many parents arealso getting ready for work, helping their children and preparing food for lunches. Butdon't forget about breakfast! When things get wildly busy in the morning, some people(36)_______ breakfast to save time. But that may be a big mistake for students Find the distance between the points (-4, -2) and (-8, 6) Miles is putting a fence around his garden. The total area of the garden is 4,864 square feet. The length of the garden is 152 feet. How many feet of fencing does he need to go around the whole garden?Help pls!! on the unit circle, which of the following angles has the terminal point coordinates of (\sqrt(2))/(2),-(\sqrt(2))/(2)a)5pi/4b)pi/4c)3pi/4d)7pi/4 What does the excerpt imply about Rome's relationship with France? What is your worst experience in your oral communication class? write down three power of Federal unit of governance according to your constitutional province Geometry, please answer question ASAP The king and queen spent $1500 on decorations for the ball +8 dollars per guest for party favors. The king and queen are charging each guest $12 to enter the dance. How many guests must come to the ball for the king and queen to break even? (you must write an equation and then solve) PLEASE HURRY!!!Find the area of the region that is NOT shaded. A telephone long distance carrier charges customers $0.99 for the first 10 minutes and then $0.09 for each minute beyond 10 minutes. If Mary uses this carrier, how long can she talk for $5.00 help plz its due tomorrow In a plane, line e is parallel to line f, line f is parallel to line g, and line h is perpendicular to line e. Which of the following cannot be true? e h g h e g h f In a particular year, a total of 46,601 students studied in two of the most popular host countries when traveling abroad. If 8483 more students studied in the most popular host country than in the second most popular host country, find how many students studied abroad in each country. There were ____ students who studied abroad in the most popular host country. Simplify: 2(6+1)-|-10|+3x2 1. ng knh ca mt loi trc my l mt i lng ngu nhin c phn phi chun N ( = 250mm, 2 = 25mm2). Trc my c gi l hp quy cch nu ng knh t 245mm n 255mm. Cho my sn xut 100 trc. Tnh xc sut :a. C 50 trc hp quy cch.b. C khng qu 80 trc hp quy cch