# Posts by anna

Total # Posts: 2,670

**chemistry**

what is the experimental errors in determining the formula unit of zinc chloride?

**math**

Thank you Henry! I really appreciate your help! :) Great!

**math**

I cant figure this thing out fully, I feel so clueless. Does anyone have any pointers or tips for me? Company needs a new copy machine. Rent costs are = 17.5 cents / each. Number of copies = atleast 200 000. (The company agrees to buy at least that number) Buying the unit ...

**Spanish**

4. ¿Qué pasa? ¿No me oyes? A) si, te oigo. B) si, les oigo. C) no, no se oigo. D) no, no me oigo. 7. Le compro un regalo para mi hermana. A) se la compro esta tarde. B) me lo compro esta tarde C) te las compro esta tarde. D) se lo compro esta tarde. 9. Te...

**Cultural Diversity**

the lanaguage learning approach of certain non-mainstream cultures seems to require children to do what in regards to human speech

**chemistry**

As a lab, we will be given a small amount of calcium and will be told to find the mass of it without using a scale( using stoichiometry or mols?) I just don't know how to do this! Thanks!

**algebra**

yes

**Math**

The length and width of the field as a ratio of 11:7. The width is 20 meters less than the length. How many m2 is the area?

**Spanish-7th grade-Please check**

hmm.. i would say 1 because the picture does not show the family actually watching t.v.

**CHEMISTRY**

If one added 130 mL of 2 M NaOH to 1 L of a buffer composed of 2.3 M NH3 and 3.2 M NH4Cl, what would be the pH of the resulting solution? The Kb of NH3 is 1.8 × 10−5.

**History**

Can i have a short summary of the spanish conquest 1492-1580? main events, ex: slave trade, colonization, etc

**7th grade math**

-2(8-4)-8(-6-8)= im notsure how to do this can someone please explain how to do this and what the answer is, i keep coming up with 2 but that's not right. i need help!

**trig**

determine all trig functions of theta using the given info, state the answers correct to the nearest hundredth. cos (theta) = -5/13; tan (theta) < 0

**Chemistry**

Calculate the theoretical pH after 2.50ml and 9.50ml of NaOH has been added in both the titration of HCl and of HC2H3O2.

**chemistry**

for the vaporization of water at 1.00 atm, delta H=43.54 kj/mol at 298 K and delta H= 40.68 kj/mol at 373 K. the constant-pressure heat capacity of liquid water is 75.3 J/molK. calculate the constant pressure heat capacity for H2O(g).

**Science**

A 7-kg brick is dragged across the floor by a horizontal force of 42 N. If a frictional force of 18 N also acts on the brick, what is its acceleration?

**Science**

To determine the mass percentage of an iron sample, the dissolved sample [iron exists at the start as iron(II)] was titrated with potassium permanganate (permanganate forms manganese(IV) oxide.)If 22.25 cubic cm of 0.0123 potassium permanganate, what is the mass percent of ...

**science**

A skateboarder initially traveling at 1.8 m/s accelerates at a rate of 1.5 m/s squared for 2.5 s. How far does the skateboarder go in this time? What is the equations used, variable solving for, and of course the solution.

**science**

If we were to watch a sunset, how long is it from the time the Sun begins to set until it is dark?

**Geometry**

Find the area of a regular octagon with a perimeter of 80 inches round to the nearest tenth

**spanish**

Using the subject “usted” and the verb in the imperative, tell your instructor three things she or he must do. Then tell your instructor two things she or he must not do. You will be graded on accuracy and pronunciation. Provide your sentences in Spanish.

**Chemistry-Plz see this DrBob**

Thank you so so much!!!

**Chemistry-Plz see this DrBob**

I am sorry I do not know what happens the symbolism, so I just deleted the symbols. Is it works for you that deleted the symbols? Using standard reduction potentials, calculate the standard Ecell, emf, for each of the following reactions. State if each reaction is spontaneous ...

**Chemistry- Please help!!**

Using standard reduction potentials, calculate the standard Ecell, emf, for each of the following reactions. State if each reaction is spontaneous or nonspontaneous. (Use the below reactions AS WRITTEN, DO NOT REARRANGE ANY REACTIONS.) You must show the two half-reactions and ...

**Chemistry- Please help!!**

Using standard reduction potentials, calculate the standard E¡Æcell, emf, for each of the following reactions. State if each reaction is spontaneous or nonspontaneous. (Use the below reactions AS WRITTEN, DO NOT REARRANGE ANY REACTIONS.) You must show the two half-...

**Chemistry**

Using standard reduction potentials, calculate the standard E¡Æcell, emf, for each of the following reactions. State if each reaction is spontaneous or nonspontaneous. (Use the below reactions AS WRITTEN, DO NOT REARRANGE ANY REACTIONS.) You must show the two half-...

**Chemistry Please help!!**

An electrochemical cell that uses the reaction Ti^3+ + 2Cr^2+ -> Ti^1+ + 2Cr^3+ Has a standard cell potential of E¢ªcell = +1.19V a. Write the two half-cell reactions. b. Determine the E¢ªred(reduction).

**Chemistry**

An electrochemical cell that uses the reaction Ti^3+ + 2Cr^2+ -> Ti^1+ + 2Cr^3+ Has a standard cell potential of E¢ªcell = +1.19V a. Write the two half-cell reactions. b. Labeling all parts and show the direction of flow of electrons. (Place the anode electrode on...

**physics**

While watching ocean waves at the dock of the bay, Otis notices that 13 waves pass beneath him in 32 seconds. He also notices that the crests of successive waves exactly coincide with the posts that are 7 meters apart. What are the period, frequency, wavelength, and speed of ...

**American government**

Lawmaking process

**US Government**

How do both Congress and special interest groups compete against the president for control of policy (mainly foreign policy)?

**math**

Luisa and Connor had $360 altogether. after conner gave Luisa 3/5 of his money, she had the same amount of money as he did. how much did conner have in the beginning?

**English**

„that helps us to become“ or „that helps us become“?

**math**

The ratio of the number of postcards john had to the number of postcards Zachary ha d was 4:9. Zachary had 45 more postcards than John. After giving some postcards to John, Zachary had 6/7 as many postcards as John. (A) How many postcards did Zachary have in the beginning? (B...

**math**

Prove eachh mathematical statement for integers m,n,k,p,a,b 12. For every prime p and nonzero n we have n^2 is congruent to nMODp if and only if either n is congruent to 1MODp or n is congruent to 0MODp.

**Algebra II-Please help!!**

Thank you for the explanation-it actually makes sense now

**Algebra II-Please help!!**

Please help-I'm really mixed up How do I find the permutations of the first 12 letters taken 3 at a time? I have a ton of these to do and really don't understand them at all-

**science**

Write a letter to persuade a friend that a change in temperature does not necessarily mean that a chemical change has occured.

**English - to JJ**

If my thesis is Social networking is a powerfull force in modern society. It helps us stay connected with friends, even if we don't show them the 'real' us and it has shaped current events and our views on these events... will my topic be about facebook or myspace...

**Programming**

Write a program to do the following: In main, declare a Player Name Array and a Score Array. Declare the size of the arrays to be 100. In the InputData( ) method, input the player name and score into the arrays for an unknown number of players up to 100. In the ...

**English**

can i get some suggestions what I should write about?

**English**

need help with thesis and topic sentences. Is this a good thesis? Social networking help change the we speak it is daily journals,send invitation to events, and meet new friends.

**precalc**

Assume that this year, n = 1, the average annual salary for women in the United States is $25,000 and that it is increasing by 5% per year, meaning that each year the salary is 1.05 times what it was the previous year. Assume that the average annual salary for men is $30,000 ...

**chemistry**

Hi, I can't figure out how to start this one. I know I need to figure out the proportions or something of that sort. Any help is greatly appreciated Thanks! Calculate ƒ¢H for the reaction NO(g) + O(g) ¨ NO2(g) given the following: NO(g) + O3(g) &...

**WRITING SKILLS PART 1**

why living in the country is beter than living in the city i think would be more informal.

**Algebra**

Can someone help me factor this problem? Generally I wouldn't have a problem doing it, but today we're supposed to factor problems without knowing what exactly to do, (Trinomial squares, difference of squares, magic diamond, etc), and it's really stumping me. For ...

**Algebra**

I'm probably letting the layout of this problem confuse me but I need help. I need to multiply and express in simplest form: (x-5/2)^3*(1/x-5)^2

**Algebra**

Hi! Today I was absent from my algebra class, and they learned how to recognize and factor the difference of two squares.. I've tried to figure it out from the book, but it's not making any sense... Can someone help? I'm trying to figure out this problem 1 - 4x^2

**English**

thank you Writeacher, Can i get some suggestions what else should I write about?

**English**

Is this a okay paragraph? Can someone help me with it? People write on their wall about their daily life in social networking because people discuss about their life and to conversation with their friends or even people we do not even know. I would go on other people’s ...

**math**

find all numbers that divide 100 with a remainder of 4. what is the largest 2-digit divisor that can divide 100 and still have a remainder of 4? find all #'s that divide 216 with a remainder of 6.

**math**

Hannah biked the following number of miles in four days. How many miles would she need to bike on the fifth day to have a mean of 5.2 miles per day? 6, 3, 4, 3

**Algebra**

Could you please help me with this linear combination? Thank you! 8x-6y=10 4x-5y=3

**Science**

Which are the keystone species from the chaparral biome

**Literature**

I need to list 6 main characteristics of British Romantic literature. Any ideas? I'd appreciate any help. Thanks.

**Geometry-8th grade**

In circle O, chords AB and CD are congruent. Ab measures 2x + y, while CD measures 16.5 Two other chords are congruent. GH equals x +2y and KL equals 13.5 I set them up like this 2x + y = 16.5 x+2y = 13.5 then I substituted-rewrote it x = 13.5-2y Then substituted 2(13.5) + y...

**Geometry-8th grade**

In circle O, chords AB and CD are congruent. Ab measures 2x + y, while CD measures 16.5 Two other chords are congruent. GH equals x +2y and KL equals 13.5 I set them up like this 2x + y = 16.5 x+2y = 13.5 then I substituted-rewrote it x = 13.5-2y Then substituted 2(13.5) + y...

**Algebra**

I need help to solve this problem by factoring: 2x^2-x-3=0

**chemistry**

an aqueous solution of ammonia has 0.8% NH3 by weight.calculate the NH3 molarity

**English**

ok thank you!

**English**

Is "brittle" an onomatopoeia?

**math**

Hitomi has a total of 30 red and blue bowling balls ate her bowling alley. Each red ball weighs 8 lb. Each blue ball weighs 9 lb. If the total mass of the blue balls is 49 lb. heavier than the total mass of the red balls, how many red balls does she have?

**algebra**

5x+5=2/10x+29

**finance**

She needs $10,000 in 7 years, making $3,500 each year, with 08% interest. Starting: $0.00 After the first year: $3,500 After the second year: ($3,500 (.08)) + $3,500 + $3,500 = 7,280 After the third year (7,280 (.08)) + $3,500 + $7,280 = 11,082.40 She has enough for a year. ...

**Trianle Fire**

What was the significance of the fire which occurred on March 25, 1911 at the Triangle Shirtwaist Company in New York City? Why were public officials motivated to act in response to the fire? How did the fire and the response to the fire impact the world today?

**ap physics**

When a rattlesnake strikes, its head acceler- ates from rest to a speed of 21 m/s in 0.46 s seconds. Assume for simplicity that the only moving part of the snake is its head of mass 200 g. How much (average) power does the rat- tlesnake need to accelerate its head that fast? ...

**ap physics**

On a frozen pond, a 7 kg sled is given a kick that imparts to it an initial speed of 3.1 m/s. The coefficient of kinetic friction between sled and ice is 0.15. The acceleration of gravity is 9.8 m/s2 . Find the distance the sled moves before coming to rest. Answer in units of m.

**ap physics**

Karen has a mass of 48.2 kg as she rides the up escalator at Woodley Park Station of the Washington D.C. Metro. Karen rode a distance of 65.7 m, the longest escalator in the free world. The acceleration of gravity is 9.8 m/s2 . How much work did the escalator do on Karen if it...

**statistics**

The average temperature in households is 67.6 degrees F. The standard deviation is 4.2 degrees F. A random sample of 51 households is to be selected (a) What is the probability that the average of this sample will be above 68.3 degrees F? Probability = (4 decimal places) (b) ...

**Art Appreciation (college level)**

Art 101 (Art Appreciation) textbook (Gardener's art through the ages) by Kleiner, F.S. 2010 The Western Perspective vol 11 (13th edition) Question: Discuss how the late Gothic sense can be seen as an evident in Berlinghieri's St. Francis Altarpiece.

**physics**

A slingshot consists of a light leather cup attached between two rubber bands. It takes a force of 32 N to stretch the bands 1.1 cm. a) What is the equivalent spring constant of the rubber bands? Answer in units of N/m.

**Chemistry**

Why AgSCN is selectively precipitated before the formation of FeSCN2+? given that Ksp of AgSCN = 1x10^-12 and Kinstab of FeSCN2+ = 7.1x10^-3

**chemistry**

If 0.1200g of sodium carbonate is dissolved in 50 mL of water and titrated with 0.1000 M HCl, how many mL of HCl will be required to reach the second endpoint? CO3^-2 + H^+1 --> HCO3^-1 HCO3^-1,+ H^+1 --> H2CO3

**Physics please help!!**

a clothes washer starts from rest and spins up with an angular accceleration of 10/rad/s^2. Determine the angle through which the washer has moved afer 6 seconds.

**precalc**

If is vector a ia 7 units long, the magnitude of vector b is 10 units and the cosine of the angle between the two vectors is -0.3 when they are placed tail-to-tail, what does the inner product of vector a and vector b equal?

**chemistry**

To what volume should you dilute 126 ml of an 7.90 M CuCl2 solution so that 49.5 ml of the diluted solution contains 5.9 g CuCl2?

**French-Simple question**

Im trying to find out what each person is studying. Every person in my text has a bubble over their heads, and in that bubble is a picture such as...one person had a bubble picture of a microscope over their heads, so that would mean that they are studing biology. What course/...

**French**

Est-ce que tu voyages beaucoup? Ou? Oui je Voyage beaucoup à Vancouver. Est-ce que tu aimes prendre des photos? No je n'aime pas prendre des photos. Est-ce qu'il y a une fete dans ta ville? Quand? Oui, il ya un festival dans ma ville et c'est le jour du ...

**Math**

Assume you work at a company where you are paid hourly. You are paid $8.60 per hour for regular time (less than or equal to forty hours) and time and a half for overtime hours up to fifty hours in one week. If you are asked to work fifty or more hours in one week you are paid ...

**English**

I'm writing for my opinion but I can't figure out what to write.

**English**

Can anyone give me details or tell me what else should I talk/ more information on something. I ran out of ideas/ thoughts. This is what I got. What media would you use for your communication skills to advertise? I would used the television for my communication skills to ...

**math (calculua)**

find the volume of the solid of revolution generated by rotating the graph of y=5lnx about the y-axis between y=0 and y=15

**math (calculua)**

find the volume of the solid of revolution generated by rotating the graph of y=5lnx about the y-axis between y=0 and y=15

**math (calculua)**

find the volume of the solid of revolution generated by rotating the graph of y=5lnx about the y-axis between y=0 and y=15

**British Literature**

Is the following statement a malapropism? "Your reason,dear venom, give thy reason".

**social studies**

My second grader is writing an essay on the blending of the American Culture. Help please!

**spelling**

thank you

**spelling**

what is the easiest definition for menace?

**Language Arts**

read

**Algebra**

3.5

**Calculus**

let f(x)=x*e^x For what value of x is the slope of the line tangent to the graph of function f at [x,f(x)] equal to 1/2?

**Calculus**

thank you!

**Calculus**

what is the slope of the tangent to the graph of f(x)= ln [cos(x)] at x= pi/6 ???

**calculus**

what is the integral of ( x^2 / (x+1)dx

**english**

I need to compare and contrast the themes of Andrew Marvell's "To His Coy Mistress" and Christopher Marlowe's "The Passionate Shepherd to His Love." Where do I start?

**algebra**

use substitution method/linear combinations to solve then tell how many solutions they have -7x+7y=7 and 2x-2y=-18

**6th grade math**

Thanks! :)

**6th grade math**

That means 4 times 1 is 4 and then multiply by 2 and so the answer is 8?

**6th grade math**

I still don't get it.

**6th grade math**

What is 4 divided by n is 1/2?