# Posts by anna

Total # Posts: 2,670

**Trigonometry (identities)**

Simplify: 1. sin(α+β)+sin(α-β) 2. (-8cosxsinx+4cos2x)^2 + (4cos^2x+8sinxcosx)^2 3. sqrt(sin^4xcosx) * sqrt(cos^3x)

**chemistry**

Answer is 40.1L. After conversions, plug it all into V=nRT/P

**chemistry**

Try PV=nRT, where R=0.08206, P=pressure, V=volume, n=moles, and T=temperature. Convert temperature to Kelvin, Torr to atm (pressure), and g to moles (divide by molar mass).

**Chemistry**

This sounds right to me! Next step to find kJ per gram, would be to convert your J to kJ, and divide by the amount of grams given. This is odd, however, since normally these problems want kJ per mole, not gram. I hope this helps!

**art**

Thanks "Sid.V" I couldn't figure out number 2

**chemistry**

Keep in mind: n=moles, so divide your grams by molar mass to get moles. Then, as said above, plug everything in. V=nRT/P

**Chemistry**

Set up: convert units --> PV=nRT --> PV/RT=n --> moles to molecules. (0.993atm*2.00L)/(0.08206*296.15K)=0.08176 mol N2 0.08176 mol*(6.022x10^23 molecules/1 mol)=4.92x10^22 molecules N2 Let me know if this helps!

**English**

B. It's for sure.

**math**

The area of a circle is given by the formula A = ðr2, where r is the radius. If increasing the radius of a circle by 1 inch gives the resulting circle an area of 100ð square inches, what is the radius of the original circle?

**History**

ohhhhh its C xD

**History**

so A :)

**History**

South Carolina .

**History**

Why did the popularity of the Grange decline? a.)Its leaders were weak and ineffective. b.) It became corrupt and lost the farmers' trust.**** c.) It did not address the farmers economic needs. d.) it was not able to obtain political power in the state

**History**

thank you mrs.sue and reed :) if i have anymore questions do you mind helping ? if not its ok i understand :)

**History**

so for the last one would it be A ?

**History**

wait would number 2 be b ? i was confused on that one . and be for the last question also ?

**History**

im confused about that last one would it be a or b ? and yes for number 1 and im not sure for number 2 because that's the whole question

**History**

please help i have my answers just not sure if im correct :( what criticism did tillman direct at conservations? a.)they controlled the office of the govnr b.)they didn't think blacks should vote ****** c.)they believed in white supremacy d.)they didn't care about the ...

**Spanish**

Hola Sra. Do these look ok? Part I Complete el párrafo por llenar los espacios en blanco con la forma correcta de los verbos entre paréntesis. ¡OJO ! No todos requieren el subjuntivo. Hoy martes estoy en el aeropuerto y tengo que pasar la aduana. El aduana ...

**Pre-Algebra**

Equation M: y = 3x + 4 Equation P: y = 3x + 7 Which of the following options is true about the solution to the given set of equations? No solution One solution Two solutions Ininite solutions I thought it was infinite solutions but i got the answer wrong.

**CHECK ANSWERS PLEASE!!!**

Thanks "Alexis" I got a 100% I had gotten them almost completely wrong smh.

**chemistry**

How much energy is needed to completely remove an electron from n = 2 in a hydrogen atom?

**Art**

Got 100% thanks

**Spanish**

Thank you so much for your tips. Hopefully these are better. 1. La fiesta se considera excesa pero todo el mundo participa. 2. Se abrazan, celebran y bromean acerca de la muerte. 3. Ella era una buena madre y estaba triste que su hijo era un ladrón. 4. Él pens&...

**Spanish**

Hola Sra.! Do these look ok? Escriba un párrafo (por lo menos 5 oraciones) para contestar cada una de las preguntas siguientes. 1. Identifique dos temas principales de “The Day of the Dead” por Octavio Paz. El ensayo es sobre la cultura de la fiesta y de la ...

**Math**

6.25

**math**

Sinx/Cscx -1+sinx/Cscx +1= 2tan^2x

**L.A**

An analogy explains, clarifies, or illustrates something by drawing comparisons. Frost compares the woods to life. The two paths represent decisions made to take one road, and not the other road. Whitman uses analogy by saying that the Civil War was a sea voyage and Mr. ...

**social studies. NEED HELP ASAP**

It's restricting their appearance. Thy wear hijabs, and long silk clothing. This is the only one that makes sense. If you read your book, it tells you about women who have jobs. They even gave an example of a woman who is nurse. Also, what Ms. Sue said. They have the right...

**Chemistry**

i converted from pKa to Ka for all three values. i don't know where to go from there.

**Chemistry**

Phosphoric acid, H3PO4(aq), is a triprotic acid, meaning that one molecule of the acid has three acidic protons. Estimate the pH, and the concentrations of all species in a 0.250 M phosphoric acid solution. [H3PO4] = ? [H2PO4^-] =? [HPO4^2-]=? [PO4^3-]=? [H^+]=? [OH^-]=? pH=?

**Math**

Three is not A. Three was C for me, and I got a one hundred. Thank you I_Was_Here.

**chemistry**

A container of gas at 24 psi is compressed to one eighth its original volume. What is the new pressure of the gas? Answer in units of psi.

**chemistry**

A chemist prepares a sample of hydrogen bromide and ﬁnds that it occupies 249 mL at 60◦C and 552 Torr. What volume would it occupy at 0◦C at the same pressure? Answer in units of mL

**Precalc+trig**

Solve tan(40/90) for the double angle cos(2theta). I know I use the x^2 + y^2 = r^2 formula and cos(2theta) = cos^2theta - sin^2theta. But I don't understand my answer

**MATH**

thank you for answering my question

**calculus**

Find Indefinite Integral of dx/(x(x^4+1)). I think that Im complicating it too much. I moved the dx out making it 1/(x(x^4+1))dx than 1/(x^5+x)dx. I think i have to use formula indef integral of dx/(x^2+a^2) = 1/a(tan^-1(x/a)) but im stuck i don't know what to do next. I ...

**chemistry**

Given the following balanced chemical equation, if 15.4 g AgNO3 are reacted, how many moles of AgCl are produced? 2 AgNO3 + BaCl2 → 2 AgCl + Ba(NO3)2

**chemistry**

A sample of oxygen that occupies 2.5 × 10−6 mL at 508 mm Hg is subjected to a pressure of 1.2 atm. What will the ﬁnal volume of the sample be if the temperature is held constant? Answer in units of mL

**Social Studies**

Thank you for the map, Ms. Sue.

**physics**

Ohh I see the pulling force is 220.5 The frictional force is 66 For the normal force I actually got 367.85 I just don't understand how you solved for acceleration by saying 1/2-1/5*7.96

**physics**

Sorry I meant 47 kg.

**physics**

For the frictional force I got 61.4 For the magnitude of the Normal force I got -398.5 and for the amount of force pulling you down the slope I got -250.2 I don't think that's right though.

**physics**

Oh sorry. To find the frictional force is it (0.18)*(47.0)(9.80)cos37 degrees and the magnitude of the Normal force is (47.0)(9.80)cos37 degrees

**physics**

Is this right? (45.0)*(9.80)*(sin35 degrees)= a number a number - frictional force = answer

**physics**

You are skiing and have a mass of 47 kg and are on a slope making an angle of 37 degrees above horizontal. The coefficient of kinetic friction between the skis and the snow is 0.18. What is the amount of force pulling you down the slope? What is your acceleration down the slope?

**statistics**

I also need help with this question!!!!

**Spanish**

Thank you Sra. Yes I got the question and answers backwards in part II. SCAMP really helps. I will add that to my notes. Thank you.

**Spanish**

Hola Sra. Are these correct? Part I Indique si las palabras dadas son sinónimos, antónimos o que no son relacionadas. 1. maletas y equipaje sinónimos 2. despegar y aterrizar antónimos 3. abrochar y confirmar no son relacionadas 4. ida y vuelta sin&...

**Social Studies**

Women politicians is the answer to 10. -Hijabs are old things that they wore all the time. -the Five Pillars I have no idea. -prayer outside the home is already one thing they do. They prey in the masque.

**english**

Mr. Bacon is right! 100%

**Math Help**

Hi! Can someone please help me with these? Thanks! :) Directions: Look for the direction angle for vector v. If necessary, round your answer to the nearest tenth of a degree. 1.) v = 8i - 10j 2.) w = -4i - 3j

**Math**

u = <7, -3> and v = <-2, 4>. Find u + 3v.

**social studies. NEED HELP ASAP**

Thanks for the help. I got 100% The answers are: 1. C 2. A 3. D

**Chemistry**

1.How much energy is emitted by 1 mol of sodium ions emitting light at this wavelength? Answer in units of kJ. This is what I did for this problem, but my answer is wrong 45.8 mg = 0.0458 g 0.0458 g / (23.0 g/mol) = 0.001991 mol Na 0.001991 mol x (6.02214 x 10^23) = 1.199 x 10...

**Art**

I got a 100% with those answers!

**Spanish**

Thank you so much Sra. These all make sense.

**Spanish**

Sra. Do these look correct? Part I LOS MANDATOS AFIRMATIVOS. Forme mandatos afirmativos directos según el ejemplo: Ejemplo: BUSCARLO (tú) Búscalo 1. CONDUCIR (Ud.) conduzca 2. PREGUNTARLES (Uds.) pregnútenles 3. COMER (nosotros) comamos 4. OLVIDARSE...

**math**

A bag contains 5 red and 4 green apples. Michael takes one apple at random from the bag. His sister Ashley then takes an apple at random from he bag. What is the probability that the two apples are the same colour? Can you explain to me how to do this please? Do I need a ...

**social studies**

What's the answer?

**Physics**

Okay, I understand now. Thank you.

**Physics**

Thanks. I didn't realize f=ma could be used because of gravity's acceleration.

**Physics**

A 2.0 kg mass is attached to a string that is 1.0 m long and moves in a horizontal circle at a rate of 4.0 revolutions per second. a) What is the centripetal acceleration of the mass? I converted 4 rev/s to 25.13 rad/s and used the equation: a=rw^2 to get 632 m/s^2 b) What is ...

**LA Check please**

Thank you so much Kristina!

**Physics**

A 50 cm diameter wheel rotates through 25 radians. How do I figure out the amount of distance it will move?

**physics**

With an average acceleration of −1.3 m/s2 , how long will it take a cyclist to bring a bicycle with an initial speed of 13.7 m/s to a complete stop? Answer in units of s.

**Math**

how would you figure out what % of people have black hair

**Math**

At a parade 1/4 of the participants have red hair, 1/6 of them have brown hair, and the rest of the participants have black hair. What fraction of the participants have black hair?

**Math**

Can you please explain how you got 2.4 and we'll keep the posts under Jordan's name. Thank yOU!!!

**math**

the answer is 7 boards

**Language arts check work**

I just got a 100% The answers are 1. C 2. A 3. C 4. A 5. A Thanks "Worker", and "Anonymous".

**Physics**

a batter hits a baseball into the air. If the horizontal component (X-component) of the velocity is measured to be 20.4 m/s, if at it's max height the ball was in the air for 2.5 s, at what angle was the ball hit off the bat?

**Physics**

a bullet is fired horizontally from the top of a cliff that is 15 m above a long lake. if the muzzle speed is 478, how far from the bottom of the cliff does the bullet strike the surface of the lake

**ART HAVING HARD TIME**

Thank you Sid.V and thank you Anonymous. I got 100%. I've been sick, and everything is turning to mush in my head. I can barely understand what I read, so I want to thank you for your help.

**Math**

397.80

**Ethics (last question)**

Thank you, Reed!

**Ethics (last question)**

I'm having a tough time with these two questions. I think I have it, based on the indicator, but I'm not positive that the reason that I listed is correct. Argument: 1) Anything is possible (you agree?) Therefore, it must be possible that something is impossible. This ...

**Social Studies**

Anonymous is right, I got 100!

**Math**

6% of what number is 10 1/2? Who would you solve this question?

**Ethics**

Thank you Ms. Sue!

**Ethics**

Are my answers correct? Please help. Thank you! 18-20) Some arguments have complex premises, where too much information is given. Outline the following argument. Some matters of foreign policy are just beyond George W. Bush’s grasp, for, like in the matter of the prison ...

**velocity**

A 0.156 kg ice puck collides with a 0.170 kg ice puck. Both were originally moving at the same speed. Which one has the larger change in velocity? Or do they have the same change in velocity?

**Finite Math**

The quantity demanded x of a certain brand of DVD player is 3000/week when the unit price p is $485. For each decrease in unit price of $20 below $485, the quantity demanded increases by 250 units. The suppliers will not market any DVD players if the unit price is $350 or ...

**physics**

A racing car has a mass of 1970 kg. The acceleration of gravity is 9.8 m/s^2. What is its kinetic energy if it has a speed of 102 km/h? Answer in units of J.

**Chemistry**

If 0.45 M of ammonia solution has a pH of 9.20, what is the H+ concentration of the solution?

**Physics and Math**

The given answer is root over 2000

**Physics and Math**

[a bullet weighing 50gm hits a 10cm wall with velocity 100ms-1 and comes out of the wall. If the frictional force on the bullet while in the wall is assumed to be a constant 2000N then with what velocity does the bullet come out of the wall?

**math**

Explain how you could use 5 x 6 equals 30 to find the product of 6 x 6p

**Last 3 QUESTIONS !!:( please**

Thank you so much!

**Last 3 QUESTIONS !!:( please**

I meant 4 and my answers are 1) by approving both through the Compromise of 1877 2) The southern economy was quickly restored to pre-Civil War levels ?? 3) Lincoln read and established the Emancipation Proclamation 4)These amendments were stepping stones to economic equality ...

**Last 3 QUESTIONS !!:( please**

How did party leaders resolve the disputed election of Rutherford B. Hayes and southern demands for removal of troops in the South? by agreeing to home rule for the South and an investigation into the election practices in several states by disapproving both through the ...

**Big History Test (Check) Part1.**

Thank you(:

**Big History Test (Check) Part1.**

Please help me, I tried answering them my best. This isn't all the questions but I wanted to do --> check -- do --> check... then done. PLEASE

**Big History Test (Check) Part1.**

What was the chief goal of the Compromise of 1850? to resolve Texas's statehood issues to preserve the Union <-- to improve the economy in both the North and the South to preserve the balance between slave states and free states What theory promoted by Congressman ...

**creative writing**

Your welcome :D

**creative writing**

What is a Volta? Volta, can be used in reference to any type of literature, but is most frequently used in regard to poems, particularly sonnets. It comes from Italian and quite literally means ‘turn’, which is why you might hear it referred to as ‘the turn’...

**creative writing**

I think its C) a change or turn in the poem A turn in a sonnet is called a volta. A vital part of virtually all sonnets, the volta is most frequently encountered at the end of the octave (first eight lines in Petrarchan or Spenserian sonnets), or the end of the twelfth line in...

**Math help...**

I got it its 7/40.

**Math help...**

The length of a rectangle is 4/5 feet. The width is 5/8 feet. How much greater is the length of the rectangle than the width?

**Math**

6 9/8 - 25/6 = = 57/8 − 25/6 = ((57 × 6) − (25 × 8)) / (8 × 6) = (342 - 200) / 48 = 142/48 = 71/24 = 2 23/24