# Posts by liz

Total # Posts: 1,301

**Calc**

The U.S. population is approximated by the function P(t) = 556 1 + 3.72e−0.5t where P(t) is measured in millions of people and t is measured in 30-year intervals, with t = 0 corresponding to 1930. What is the expected population of the United States in 2020 (t = 3)? (...

*July 19, 2012*

**psychology**

how effective is classical conditioning in the long tem

*July 15, 2012*

**economics**

Why might management and economic theories not always work in the real world?

*July 13, 2012*

**economics**

A copy company wants to expand production. It currently has 20 workers who share eight copiers. Two months ago, the firm added two copiers, and output increased by 100,000 pages per day. One month ago, they added five workers, and productivity also increased by 50,000 pages ...

*July 13, 2012*

**Math**

Joe drank 4 liters of water on Monday and 4 deciliters of water on Tuesday. How much more water did he drink on Monday than on Tuesday?

*July 10, 2012*

**Calculus**

Find if the limit exists. lim tan(x)/x x->0 Please show how you determined this. Thanks!

*July 1, 2012*

**Calculus**

Find an equation of the line that is tangent to the graph of f and parallel to the given line. Funtion: f(x)=1/sqrt(x-1) Line: x+2y+7=0

*June 30, 2012*

**Calculus**

**Note** Please use the Epsilon-Delta Definition.

*June 27, 2012*

**Calculus**

I have two similar problems that I need help completing. Please show all your work. Question: Find the limit L. Then use the å-ä definition to prove the limit is L. 1. lim (2x+5) x->3 2. lim 3 x->6 Thank you for your anticipated help!!

*June 27, 2012*

**Algrebra 1**

What are the practical uses of scientific notation? Why is scientific notation so important in modern-day society?

*June 26, 2012*

**english**

They are going to the park and play or they are going to the park to play. Which one is correct.

*June 26, 2012*

**english**

There are never enough discipline on the playground: someone always is getting hurt. Subject verb agreement.

*June 26, 2012*

**Grammar**

Everything looks good except #3, it is supposed to be Was.

*June 21, 2012*

**reading**

You don't want to put your the title of the essay in the introduction. An introduction has to have a grabber, thesis statment and also an idea of what we'll be reading. Sometimes that idea is part of th egrabber and that makes it stronger. People would want to read it...

*June 21, 2012*

**reading**

It looks like there are supposed to be choices. maybe if you put the choices down we'll help.

*June 21, 2012*

**Chemistry (1Question)**

This is really confusing. I know how to do the equilibrium which also has to do with reaction rates but they didb't give it to me as a choice. Please Please help me. I post other questions that i answered already but no one answered me. I just needed someone to check them ...

*June 21, 2012*

**To DrBob222(Please check Chem)**

#4 is the last choice for sure. I googled exothermics and i even found examples. #'s 12 and 14 look wrong to me also but those are the only choices i got.

*June 21, 2012*

**To DrBob222(Please check Chem)**

(This homework question has been removed due to a copyright claim submitted by K12 Inc.)

*June 21, 2012*

**Algebra(please help)**

Will someone please help me withthis question I couldn't solve it. What is the length of the segment whose endpoints are A(2, 3) and B(10, 7)? a)2 Sqrroot29 b)2 Sqrroot41 c)4 Sqrroot2 d)2 Sqrroot5

*June 19, 2012*

**Calculus**

Find the volume of the solid generated by the region in the first quadrant bounded above by the 3x+y=6, below by the x-axis, and on the left by the y-axis, about the line x= -2.

*June 3, 2012*

**chemistry**

The data in the table show the amount of a 500 g sample of sodium-24 over time. Make a graph of the data (remember to label all axes and title the graph). What is the half-life of sodium-24? Explain how you determined your answer. Sodium-24 decays by beta emission. Write a ...

*May 29, 2012*

**English (quick Sentence)**

Thanks. I forgot the comma ansd i used tha present tense when it is supposed to be the past tense.

*May 29, 2012*

**English (quick Sentence)**

Hi Teachers, I wrote a sentence in which i think has a wrong sentence structure. Will you correct me with it, please? When his daughter told us of what he said we promised that we will all be in part of helping him and making him feel like family.

*May 29, 2012*

**Comm 215**

Part1 looks good to me. I have to go:( I hope you get help with the rest.

*May 29, 2012*

**English**

It would be at the end of the cited work.

*May 28, 2012*

**English (Check Please)**

Hi Teachers, will you please check my answers? The arrows indicate my answers. Am I right? 1. The speaker’s use of many exclamation points and imperative statements in “Beat! Beat! Drums!” helps readers feel the tone’s humor. urgency. <--- quiet calm. ...

*May 28, 2012*

**English**

Type this question in bing and when the results come up it is the first one. very helpful paper, trust me! Where would i put a parenthetical citation for a work that needs to be credited? This is what you should press on. Parenthetical (in-text) Documentation (citation)

*May 28, 2012*

**English (Check)**

Thank you again Ms. Sue.

*May 28, 2012*

**English (Check)**

Thank you so much for your help Ms. Sue. I had already told my sister that i think it is abundance and energy because in thos lines it talks about the coolness and sweetness of Ohio. It also talks about the flutering leaves in a moderate wind. She thought i was wrong. Thank ...

*May 28, 2012*

**English (Check)**

Would it be suffering and loss? I'm just confused by this question.

*May 28, 2012*

**English (Check)**

I'm sorry i forgot to tell you that the arrows means indicate my answers. Am i correct?

*May 28, 2012*

**English (Check)**

Hi Teachers, will you please check my answers? 1. The speaker’s use of many exclamation points and imperative statements in “Beat! Beat! Drums!” helps readers feel the tone’s humor. urgency. <--- quiet calm. high spirits. 2. With what kind of life are ...

*May 28, 2012*

**Religion**

Hi Rebecca, I am a Muslim and Islam promotes peace. May i ask, what made you ask this question?

*May 28, 2012*

**Calculus**

Find the volume of the solid of revolution by roating the region R about the y-axis. Write the answer as a multiple of pi. y= sqrt(x), y=x^2, in the first Quadrant

*May 27, 2012*

**Chemistry**

In a calorimeter, 100 g of ice melts at 0oC. The enthalpy of fusion of the ice is 334 J/g. How much heat was absorbed? 33.4 J 334 J 33.4 kJ 334 kJ

*May 26, 2012*

**English ASAP**

I have to choose the sentence that has no error in italics. (Italicized) a)Their lawyers are handling the case pro bono and not charging them a dime. b)Yes, of course you can use (and) instead of a comma here. c)Oh, I see the problem; this (three) should be an (eight) <-- I...

*May 23, 2012*

**chemistry**

a student determines the molar mass of methanol by the method used in this experiment. she found that the equilibrium temperature of a mixture of ice and pure water was .4 degrees Celsius on her thermometer. when she added 10g of her sample to the mixture, the temperature, ...

*May 22, 2012*

**Calculus**

A container is in the shape of an inverted right circular cone has a radius of 2 in at the top and a height of 6 in. At the instant when the water in the conatiner is 5 in deep, the surface level is falling at the rate of -.4 in/s. Find the rate at which the water is being ...

*May 17, 2012*

**Calculus**

Find the third Derivative of f(x)=x(3x-7)^3 The answer is 3x-1134 but I attempted the problem multiple times and I keep ending up with 648x-1134. What am I doing wrong?

*May 17, 2012*

**Algebra2 {ASAP}**

Hi helper, I used permutation for the following question. How can i use combination to find the answer? Help me please! There are 12 red checkers and 3 black checkers in a bag. Checkers are selected one at a time, with replacement. Each time, the color of the checker is ...

*May 17, 2012*

**social studies 9**

Wouldn't this be reading or Literature? I think that Dickens gave him his name because he looks a bit chubby and is short. More like a bumble bee with a fat stomach. It is just a good guess and that is how i visulized him whem i read Oliver Twist by Charles Dickens.

*May 17, 2012*

**Algebra**

thank you! u r awesome... I wasn't too sure.. again thank you!

*May 16, 2012*

**Algebra**

Use the formula d=rt to find the value of the missing variable d=42 feet, t=14 seconds then r= ft. second

*May 16, 2012*

**MAT 116 (algebra)**

Please help not understanding this question. If the cost of a cell phone has decreased 400% during the past 10 years, does that correspond to a cost decrease of four times? Make up your own numbers in an example and then explain your answer as though you were talking to ...

*May 15, 2012*

**8 th grade**

Good job.

*May 14, 2012*

**English**

The styles are different. The “ Theme for English B” is a free style and the “Ballad of Birmingham' has rhythm. The rhythm he uses is ABCB, ABCB and so on. The themes for both the “Theme for English B” and “Ballad of Birmingham” are civil...

*May 13, 2012*

**English**

Well i understand that the style for “Theme for English B" is a free style. I don't know what style a “Ballad of Birmingham” uses. I know that it is something like ABCB but i don't know what the name is for it. I'm thinking that the theme for ...

*May 13, 2012*

**English**

How do the styles and themes of “Theme for English B” and “Ballad of Birmingham” compare? Answer this question in at least a paragraph and make sure to cite examples from the text. Answer:

*May 13, 2012*

**chemistry**

Given the consentration of either hrgrogen ion or hydroxide ion, use the product constant of water to calculate the consentration of the other ion at 298 K. A: [H+]=1.0x10^-4M B: [OH-]= 1.3x10^-11M

*May 11, 2012*

**Chemistry**

If a total of 13.5 mol of NaHCO3 and 4.5 mol of C6H8O7 react, how many moles of CO2 and Na3C6H5O7 will be produced? 3NaHCO3(aq) + C6H8O7(aq) > 3CO2(g) + 3H2O(s) + Na3C6H5O7(aq)

*May 6, 2012*

**Calculus**

The strength of a beam with rectangular corss-section is directly proportional to the product of the width and the square of the depth (thickness from the top to bottom of the beam). Find the shape of the strongest beam that can be cut from a cylindrical log of diameter d= 3 ft

*May 5, 2012*

**Physics**

Thank you!!

*May 3, 2012*

**Physics**

The total charge in an electrical circuit as a function of time is given by q=t/t^2+1 coulombs. Find the maximum charge q. Please provide your reasoning.

*May 3, 2012*

**Algebra 1**

3x + 4y = -2 and 2x - 3y = 10

*May 2, 2012*

**chemistry**

Calculate the pH of a 2.5x10-5 M lithium hydroxide solution.

*May 2, 2012*

**Chemistry-Help**

An AM radio station broadcasts at 1060 kHz. Calculate the wavelength of the corresponding radio waves. How do I calculate this?

*April 30, 2012*

**Algebra**

3. There are 12 red checkers and 3 black checkers in a bag. Checkers are selected one at a time, with replacement. Each time, the color of the checker is recorded. Find the probability of selecting a red checker exactly 7 times in 10 selections. Show your work. Help! I'm ...

*April 27, 2012*

**chemistry**

1.16 x 10^22 sulfur atoms

*April 24, 2012*

**chemistry**

73.7g

*April 24, 2012*

**chemistry**

how many sulfur atoms are in 2.57 g of iron (III) sulfate?

*April 24, 2012*

**chemistry**

how many grams of magnesium carbonate are in a sample that has 1.58 x 10^24 oxygen atoms?

*April 24, 2012*

**AP Chemistry**

What is the pH of a .20M HA solution (Ka=1.0x10^-6) that contains a 0.40M NaA?

*April 23, 2012*

**chemistry**

What would the pressure be if h3 po4 was vaporized in a 20L container at a temperature of 23.5 degrees Celsius?? ( gas law)

*April 22, 2012*

**Math**

oops I meant length of AB

*April 17, 2012*

**Math**

An electric circuit has equally spaced parallel wire with connections A, B, and C. If the length of AP = 3.42 cm, what is the length of BC?

*April 17, 2012*

**Calculus**

Please help!! I keep solving this problem but I keep getting the wrong answer. Find the derivative of the function: f(x)= xsqrt(x-1)/(x+2)

*April 17, 2012*

**Calculus**

A electric circuit board has equally spaced parallel wires with connections at points A, B, C. If the length of AB=3.42 cm, what is the length of BC?

*April 16, 2012*

**Native American Studies**

OR d) All of the answers are correct

*April 16, 2012*

**Native American Studies**

a) Using a sacred site to store toxic waste b) Barring development on a sacred site c) Passing federal legislation to return sacred sites to Native American control All of the answers are correct

*April 16, 2012*

**Native American Studies**

Which of the practices listed is an example of an activity Native American people might regard as an act of desecration?

*April 16, 2012*

**Calculus**

Please help!! Differentiate: y=(x^2-1)^(1/2)/x^2

*April 15, 2012*

**Calculus**

Please Help! I tried doing this on my own and got the wrong answer. Differentiate: y=4/(x-x^2)^(1/4)

*April 15, 2012*

**math**

if 11% of the population is left handed, what is the porbability that as least one of the first 20 strangers you meet is left handed

*April 5, 2012*

**math (integers)**

What interval would you use on a line graph that's range is +13~+42?

*April 2, 2012*

**physics**

A baseball is tossed at a steep angle into the air and makes a smooth parabolic path. Its time in the air is t and it reaches a maximum height h. Assume that air resistance is negligible. a.) Show that the height reached by the ball is gt2 (square) /8. b.) If the ball is in ...

*March 30, 2012*

**physics**

A rock thrown horizontally from a bridge hits the water below at a horizontal distance x directly below the throwing point. The rock travels a smooth parabolic path in time t. A.) Show that Therapy vertical distance of the bridge above water is 1/2gr2. B.) What is the height ...

*March 29, 2012*

**chemistry**

Write the correct equation for the formation of a white precipitate on mixing together 10 mL each of 1 M calcium chloride, 1 M calcium bromide, 1 M calcium nitrate, 1 M sodium carbonate, 1 M potassium carbonate, and 1 M rubidium carbonate.

*March 27, 2012*

**Chemistry**

What is the number of bonding electrons and the number of nonbonding electrons in the structure of BeF2?

*March 14, 2012*

**Chemistry**

during a molar volume of oxygen experiment indicate how each of the following errors would affect (increase, decrease, or no change) your calculated value for the molar volume of O2 at STP. 1.) Your sample was not completely decomposed. 2.) After you finish heating sample & ...

*March 7, 2012*

**Chemistry**

1. As a research chimst, you are intrested in studying the extent and type of interactions in aqueous salt solution. As part of this study, you weight three samples of NaCl and dissolve each in 1.000kg H2O. You then measure the freezing temp. of each solution and compare these...

*March 5, 2012*

**17**

BBBBBBBBB

*March 4, 2012*

**12**

D?

*March 4, 2012*

**1**

^^ Is that really necessary?

*March 4, 2012*

**Chemistry**

In our lab we had to experiment with an apparatus in order to find such things as the percent of KClO_3 in the solution.. Assume that you heated your sample too rapidly and some of the sample spattered onto the rubber stopper of the test tube. Will your calculated percent ...

*March 3, 2012*

**math**

so its 3456?

*March 2, 2012*

**math**

what is the volume of the stereo speaker 24inchs 12inches 12inches

*March 2, 2012*

**geometry**

Alec used 8 cubes to make this square frame that has 3 cubes on each side. If he uses 16 cubes to make a square frame, how many cubes will be on each side of the frame

*March 2, 2012*

**Science**

If a man has a mass of 90 kg on earth, what is his mass on the moon?

*March 1, 2012*

**Algebra II**

Simplify - 2/(the 6th root of 81)

*March 1, 2012*

**algebra**

Simplify - 2 / (the 6th root of 81)

*March 1, 2012*

**Math-Are my answers correct?**

Thank you very much:)

*February 28, 2012*

**Math-Are my answers correct?**

An anagram is a rearrangement of all the letters in a word. Example: page--->gape, pgea.. a) Find the number of 7 letter anagrams possible for the letters in GUITARS. I did 7!=5040...is that correct? b) Find the probability of randomly choosing an anagram that starts with T...

*February 28, 2012*

**Math for the middle school and elementary teacher**

Thank you very much for you help:)

*February 28, 2012*

**Math for the middle school and elementary teacher**

3 red balls, 4 green balls, and 5 yellow balls are in a bag. If 2 balls are drawn randomly (without replacement) find the probability that the balls are different colors. I got 47/66 that the balls are different colors...is that right?

*February 28, 2012*

**math for the middle school and elementary teacher**

Thank you! :)

*February 28, 2012*

**math for the middle school and elementary teacher**

No, so that a) is the correct answer because order matters in the line! I am correct, right? Thank you very much:)

*February 28, 2012*

**math for the middle school and elementary teacher**

They are not different but for a) the order doesn't matter for the way that the people can be lined up. But for b) order wouldn't matter either because there it doesn't matter who is on which team. Then c) there are no specifed posistions for the committee I'm ...

*February 28, 2012*

**math for the middle school and elementary teacher**

I think that the answer is d) the number of different fruit salads made by choosing four out of seven fruits because you can't have all of the same fruit in a fruit salad.

*February 28, 2012*

**math for the middle school and elementary teacher**

Which one of the following situations a permutation? a) the number of ways 10 people can be lined up in a line for basketball tickets. b) The number of possible four member bowling teams from a family of six siblings. c) The number of ways to choose a committee of three from ...

*February 28, 2012*

**Math for the middle school and elementary teacher**

The answer is 79, correct? Thank you for your guidance and help:)

*February 28, 2012*