Tuesday

February 9, 2016
Total # Posts: 3,151

**Prob ans stat**

Let x be a random variable that represents the length of time it takes a student to complete a take-home exam in Dr. Larson's psychology class. After interviewing many students, it was found that x has an approximately normal distribution with mean of 5.2 hours and ...
*July 29, 2011*

**Statistics(Please check)**

calculate the probability of the following: A four, three, or spade from a single draw from a 52 card deck. there are 4 4's so 4/52, 4 3's so 4/52 and then 13/52 spades so 21/52 but and one 4 and one 3 are from spades so minus 2 = 19/52 Is this correct?
*July 23, 2011*

**Statistics(Ugent Please help!!)**

Nevermind I figured it out
*July 23, 2011*

**Statistics(Ugent Please help!!)**

Assume that 100 subjects received one of four treatment combinations and produced the data reported below. Conduct a two-factor ANOVA and complete an ANOVA table reporting the relevant SS, df, MS, F's. N=100 n=25 the table shows A1 and A2 at the top and B1 and B2 on the ...
*July 23, 2011*

**Statistics(Please help)**

Assume that 100 subjects received one of four treatment combinations and produced the data reported below. Conduct a two-factor ANOVA and complete an ANOVA table reporting the relevant SS, df, MS, F's. N=100 n=25 the table shows A1 and A2 at the top and B1 and B2 on the ...
*July 23, 2011*

**chemistry**

A sample of metallic element X, weighing 4.315 g, combines with 0.4810 L of Cl2 gas (at normal pressure and 20.0¢ªC) to form the metal chloride with the formula XCl. If the density of Cl2 gas under these conditions is 2.948 g/L, what is the mass of the chlorine? The ...
*July 22, 2011*

**chemistry**

A sample of metallic element X, weighing 4.315 g, combines with 0.4810 L of Cl2 gas (at normal pressure and 20.0¢ªC) to form the metal chloride with the formula XCl. If the density of Cl2 gas under these conditions is 2.948 g/L, what is the mass of the chlorine? The ...
*July 22, 2011*

**Statistics(Please help)**

thank you
*July 21, 2011*

**Statistics(Please help)**

the problem asks to complete an ANOVA table and report the relevant SS, df, MS, and F values, and find the critical value for the F-values. I found my F values: they were 3 and 16. I do not understand how to find the critical value.
*July 21, 2011*

**Math/Algebra**

The length of Karen's living room is 2ft longer than the width. The perimeter is 80ft. Find the length and the width. Can someone please explain to me how you find the answers? Thanks a ton!
*July 17, 2011*

**chemistry**

After you preform your experiment, you determine that the Kf value for naphthalene is 6.9 . You are using 10g of naphthalene and added 1.0 g of your unknown. The the freezing point of the solvent decreased by 4.42 when the unknown was added. Knowing this information, determine...
*July 17, 2011*

**chemistry**

Strontium has density of 2.64 and crystallizes with the face-centered cubic unit cell. Find the radius of the strontium atom
*July 10, 2011*

** chemistry**

How much heat (in ) is evolved in converting 1.00 of steam at 150.0 to ice at -55.0? The heat capacity of steam is 2.01 and of ice is 2.09 .
*July 10, 2011*

** chemistry**

How much heat (in ) is evolved in converting 1.00 of steam at 150.0 to ice at -55.0? The heat capacity of steam is 2.01 and of ice is 2.09 .
*July 10, 2011*

**chemistry**

Benzene has a heat of vaporization of 30.72kJ/mol and a normal boiling point of 80.1 C. At what temperature does benzene boil when the external pressure is 490 ? I think I have the equation setup, but I can't figure out how to solve for T2..please help
*July 10, 2011*

**statistics**

thank you!!!
*July 6, 2011*

**statistics**

calculate the correlation for data set A. Data Set A: xi = 65, 55, 50, 45, 35 yi= 44, 52, 68, 20, 36 I know how to find the mean, variance, standard deviation, and z-score. The part I am having trouble finding is the ZxiZyi. In the chart that I have to fill in it says Zxi in ...
*July 6, 2011*

**economics**

What is the role of economic theory in the way economies are run today? I need some concrete examples.
*July 6, 2011*

**Statistics(Please help)**

I have a chart that has 4 columns across the top and 33 going down. The colunms on the top read: predicted number, selected number, (col 1 - col2)^2, and the mean of x. Their are 32 predicted numbers and 33 selected numbers. I need to fill in the column that says the mean of x...
*July 2, 2011*

**Statistics(Urgent!Please help)**

I have a chart that has 4 columns across the top and 33 going down. The colunms on the top read: predicted number, selected number, (col 1 - col2)^2, and the mean of x. Their are 32 predicted numbers and 33 selected numbers. I need to fill in the column that says the mean of ...
*July 1, 2011*

**Statistics**

I have a chart that has 4 columns across the top and 33 going down. The colunms on the top read: predicted number, selected number, (col 1 - col2)^2, and the mean of x. Their are 32 predicted numbers and 33 selected numbers. I need to fill in the column that says the mean of ...
*June 30, 2011*

**Statistics**

I have a chart that has 4 columns across the top and 33 going down. The colunms on the top read: predicted number, selected number, (col 1 - col2)^2, and the mean of x. Their are 32 predicted numbers and 33 selected numbers. I need to fill in the column that says the mean of x...
*June 30, 2011*

**Chemistry**

yep its right
*June 5, 2011*

**maths**

5x10^2 divide by 7x10^4 what is the answer in standard form
*June 5, 2011*

**maths**

expand 5(3w^2+4)
*June 5, 2011*

**Calculus**

Find the definite integral that represents the arc length of the curve y=sqrt(x) over the interval [0, 3]
*May 26, 2011*

**Calculus**

Find the volume of the solid formed by revolving the region bounded by y=x^3, x=2 and y=1 about the y-axis. Please help =(
*May 26, 2011*

**Spanish**

How do you say she was looking at the tv in Spanish. I know this is in the imperfect progressive but ver ( to look) is irregular in the imperfect . Does that matter? Would it be esta viendo a la tele?
*May 25, 2011*

**chemistry**

Calculate the E° for each of the following reaction. Decide whether each is product-favored in the direction written 2 Cl-(aq) + Cu2+(aq) --> Cu(s) + Cl2(g) i got -1.020 but its wrong and i do not know why.
*May 12, 2011*

**chemistry**

From the indicated voltages for the voltaic cell pictured, determine the standard electrode potential, E°M3+/M, if the metal, M, is each of the following. description on the image: in the left beaker there is one Cr3+ and one Cr2+ on the right beaker there is 'M'3...
*May 12, 2011*

**Probability NEED HELP**

1. When two fair dice are tossed, what is the probability of a sum of 4 or a sum of 8? 2. When two fair dice are tossed, what is the probability of doubles or a sum over 9? 3. Evaluate 1025! / 1022! Please help
*May 11, 2011*

**Probability**

1. When two fair dice are tossed, what is the probability of a sum of 4 or a sum of 8? 2. When two fair dice are tossed, what is the probability of doubles or a sum over 9? 3. Evaluate 1025! / 1022! Please help
*May 11, 2011*

**Chem**

2 Ag+(aq) + Fe(s) --> 2 Ag(s) + Fe2+(aq) In which directions do the cations and anions migrate through the solution? cations toward the silver cathode or toward the iron cathode thanks
*May 11, 2011*

**Chemistry**

i have a follow up question: In which directions do the cations and anions migrate through the solution? toward the silver cathode ? or toward the iron cathode ? so do the anions(Fe)migrate to the silver? and cations toward the iron? there is a diagram that goes along with ...
*May 10, 2011*

**Chemistry**

oh ok i see! thanks!
*May 10, 2011*

**Chemistry**

Im having trouble on a question Im not sure what it is they are asking for. A voltaic cell similar to that shown in Figure 20.5 is constructed. One electrode compartment consists of a silver strip placed in a solution of AgNO3, and the other has a iron strip placed in a ...
*May 10, 2011*

**Grammar**

Does this sentence make sense, if not how do you write it correctly Never give up to your dreams? Thank you!
*May 7, 2011*

**Grammar**

Is the capital word used right in this sentence, if not how can i use it with the same meaning of the sentence His song was SKEPTICAL because it was so good Thank you!
*May 7, 2011*

**CHEM**

An atom at the face of a unit cell is shared by how many unit cells? 1 2 4 6 8
*May 4, 2011*

**Math**

o ok thank you.
*May 1, 2011*

**Math**

1) evaluate: integral of (3x^2 + 5x - 1 + 3/x) dx x^3/3 + x^2/5 - x Is this correct? 2) evaluate: integral of (5e^7x + srqtx) dx I am not sure with this. Could you please explain. Thank you for you help!
*May 1, 2011*

**Math**

for number 2 how did you get 2e^2x?
*May 1, 2011*

**Math**

1) evaluate integral of xe^3x dx 2) evaluate integral form 1 to 0 of 4e^2x dx I just need help finding the anitderivative. Would it be 2e^2x?
*May 1, 2011*

**math**

thank you
*May 1, 2011*

**math**

Deifferentiate: y=e^-3x+2 would the answer be -3e^-3x+2 or 3e^-3x+2
*May 1, 2011*

**Math(Please help. Thank you)**

thank you
*May 1, 2011*

**Math(Please help. Thank you)**

1)evaluate: integral of x ln 4x dx 1/2 x^2 + 2x^2 Is this correct? 6) evaluate the integral from 3 to 1 of x^3 - 3x +1 1/4x^4 + 3/2 x^2 Is this the correct antiderivative?
*May 1, 2011*

**Math(Please help. Thank you)**

Is number 3 considered a related rates problem?
*May 1, 2011*

**Math(Please help. Thank you)**

Are the rest that I did do correct?
*May 1, 2011*

**Math(Please help. Thank you)**

solve the following for x. 1)e^x^2-x=e^2 x^2-x = 2 I am not sure what to do now 2) e^-5x * e^4 = e -5x + 4 = 1 x= 3/5 3) Suppose that the price p (in dollars) and the demand in x(thousands) of a commodity satisfy the demand equation 6p + x + xp =94. How fast is the demand ...
*May 1, 2011*

**Math(Please check. Thank You)**

Thank you!!
*April 30, 2011*

**Math(Please check. Thank You)**

1) solve:e^x(x^2-4)=0 e^x=0 and then (x+2)(x-2) so x=2, -2 2) differentiate: y=ln(6x^2 - 3x + 1) 1/(6x^2 - 3x + 1) * 12x-3 3) differentiate: y=e^-3x+2 -3 * e^-3x+2 4) evaluate: 2^4-x=8 2^4-x = 2^3 4-x = 3 -x=-1 so x=1 5) differentiate: x^3 + y^3 -6 =0 3x^2 + 3y^2 6) A ...
*April 30, 2011*

**Math**

Determine the integral by making an appropriate substitution integral of 8x cuberoot srqt(4x^2-9) dx let u= 4x^2-9 du= 8x dx I do not know what to do now
*April 30, 2011*

**Math(Please check)**

evaluate the integral integral of 3 to 2 x/(x^2-2)^2 dx u=x^2-2 du=2x dx 1/2 du = x dx integral of 1/u^2 du -1/(x^2-2) Then I plug in 3 and 2 and subtract them form each other -1/(3^2-2) - (-1/(2^2-2) Is this correct?
*April 30, 2011*

**Math(Please help)**

Determine the integral by making an appropriate substitution integral of 8x cuberoot srqt(4x^2-9) dx let u= 4x^2-9 du= 8x dx I do not know what to do now
*April 30, 2011*

**Math(Please help)**

o I think I know. Is it because you add 1 to the x^2 which is x^3 and the inverse 1/3 you multiply by 4 to get 12
*April 30, 2011*

**Math(Please help)**

Find: the integral (x^2/4 - 4) dx I know that the answer is x^3/12 -4 +c but I do not know how to get this
*April 30, 2011*

**Math(Please help)**

Logarithmic differentiation f(x)=(2x-1)^-2 (x+3)^4 at x=1 f'(x)= -2*2/2x+1 + 4*1/x+3 [(2x-1)^-2)(x+3)^4 and then I plug in 1. I am having trouble getting an answer when I plug in 1.
*April 30, 2011*

**Math(Please help)**

1) where is the function f(x)= 5 / (2x-4)^3 increasing. I know the answer is for all of x but I do not know how to get this. I know that you can write the equation as 5(2x-4)^-3 2) Let a, b, and c be fixed with a>0 and let f(x)=ax^2 + bx + c. Which of the following ...
*April 30, 2011*

**Math(Please help)**

For the first question how did you get 800/64 and 640/64?
*April 30, 2011*

**Math(Please help)**

so 0.006(9.30)^2 - 0.02(9.30) + 0.50
*April 30, 2011*

**Math(Please help)**

1) h(t)=20(5/8) - 16(5/8)^2 + 10 = 65/4 All I need to know for this is how to calculate the fraction parts to get 65/4. I am not good with fractions. 2) A manufacturer's profit from producing x units of a product is given by P(x)=0.002x^3 - 0.01x^2 + 0.5x. At what ...
*April 30, 2011*

**Math(Please help)**

f(x,y)=x^2 e^2x lny (2,1) I need to find the partial derivatives with respect to x and y. I have not idea how to do this especially with the (2,1).
*April 29, 2011*

**Math(Please help)**

f(x,y)=x^2 - y^2 a)partial derivative with respect to x. So this means that you hold y^2 constant so would that be 0. So the answer would be 2x? b) partical derivative with respect to y. 2y
*April 29, 2011*

**Math(Please help)**

for the first one how did you get (3x^2)?
*April 29, 2011*

**Math(Please help)**

Evaluate: f(x,y)=2x^3e^y a) partial derivative with respect to x. I know that you have to treat y as a constant but I have no idea what to do. I do not understand partial derivatives at all. Please help!! b) partial derivative with repsect to y.
*April 29, 2011*

**Math(Please check)**

You invest $3000 in a savings account where you earn 4% interest compounded continuously a) what is the formula A(t) for the balance after t years? A(t)=3000e^0.04(t) b) How long will it take for the money to double? 6000=3000e^0.04t Is this the correct setup so far or would I...
*April 29, 2011*

**math(Please check)**

Also, solve: ln(x^2-5)=0 take e of both sides x^2-5=1 x^2=6 x=sqrt6 Is this correct?
*April 29, 2011*

**math(Please check)**

Find the derivative of the following: 1=x^2+4xy+4y My answer is 2x. Is this correct?
*April 29, 2011*

**Math(please check)**

1) Differentiate the following: a) y=(x^3+5x)^6 (x^2+1)^7 (6(x^3+5x^)^5 * 3x^2+5) + (7(x^2+1)^6 *2x) * (x^3+5x)^6 b) y=(x+1)^2 / x^2 (2(x+1)*1) * (x^2) - 2x *(x+1)^2 all over (x^2)^2 Are these correct?
*April 29, 2011*

**Math(Please help)**

Would the equation be y-6=15(x-2)?
*April 29, 2011*

**Math(Please help)**

Write the equation of the tangent line for the curve y=x^3+3x-8 at point (2,6) Would I take the derivative of the equation and then plug in 2 and then plug everything into y-y1=m(x-x1)?
*April 29, 2011*

**Math(Please check)**

ok thank you
*April 29, 2011*

**Math(Please check)**

yes, 3b is (pi^2)x. I do not understand why the first derivative is pi^2.
*April 29, 2011*

**Math(Please check)**

1) Find the equation of the following lines: A)Through the point (-4,2) and perpendicular to the line y=-1/2x +1 y-y1=m(x-x1) The reciprical of -1/2 =2 So my answer is y-2=2(x+4) or simplified y=2x+10 B)Through the point (1,1) and parallel to the line 5y=15x+25 so y-1=15(x-1) ...
*April 29, 2011*

**8th grade physics/science**

assume you are standing on a dock and watching the waves pass directly under where you are standing. You count the number of seconds it takes w1,w2,w3 and w4 to pass directly below you. you determine that all four waves below you in two seconds. info: in the formula the length...
*April 28, 2011*

**Food**

How did the Wrigley company come up with the name of orbit gum??
*April 28, 2011*

**chemistry**

Thanks!
*April 25, 2011*

**chemistry**

Neutralization Reaction Molarity Calculations: For example: What is the molarity of a Ca(OH)2 solution if .032 L of the solution is exactly neutralized by .015 of a 0.56 M HCl? How do I solve- I am unsure where to begin.
*April 25, 2011*

**analogy**

arson:crime rose:_________ It must be 7 letters long.
*April 25, 2011*

**College math/bus calc**

A rectangular-shaped garden has one side along the side of a house. the other three sides are to be enclosed with 60ft of fencing. what is the largest possible area of such a garden?
*April 25, 2011*

**chemistry**

how do i convert delta T to freezing point?
*April 25, 2011*

**chemistry**

The molal freezing point constant for water is 1.86 C/m. at what temperature will a micture of 2.00g of CalCl2 and 25.0g of water freeze?
*April 25, 2011*

**Math**

I am having trouble figuring out how to do partial derivatives. I have tried practice problems and have read my textbook but I am still so confused. Could someone please explain how to do this? Thank you.
*April 21, 2011*

**math**

the expiremental probability that ryan will have math homework on a given school day is 80%.on how many of the next30 school days can ryan expect to have math homework?
*April 19, 2011*

**Math-Geometry**

dont you just add all of it and then you put that number on the bottom and then you have the red and green and then you put it on top of the fraction and then multiply and simplify
*April 19, 2011*

**english**

so i posted a question very similar to this yesturdya but i have now have a more spesific question. do you guys know any poems about or from the 1950's that talks abuot basic life..
*April 18, 2011*

**English**

For a project im writing about 1950's food and the food that was unique to that time. But, in my report i also have to compare a literary work to the information i find on 1950's food. my teacher said the best work would be like a poem, song, article about your ...
*April 17, 2011*

**Math(Please help)**

Never mind I got it.
*April 17, 2011*

**Math(Please help)**

what would 8^2/3 be. 2^3 = 8 so would it be 2?
*April 17, 2011*

**Math(Please help)**

Oh, I see. Thank you
*April 17, 2011*

**Math(Please help)**

f(x,y)= 10x^1/3 y^2/3 Compute (27,64) so 10(27)^1/3 * (64)^2/3 10 * (27)^1/3 * (64)^2/3 I know that the answer is 480 but I am having a hard time calculating 27^1/3 and 64^2/3.
*April 17, 2011*

**math**

how to solve 2x+3y=17 3x+y=31 then 2(x-3y) y=3x-2 then the last one 2(x+4) x+y=17 please help
*April 17, 2011*

**Literature**

ok thank you again!!
*April 14, 2011*

**Literature**

so this story is basically about southern humor and story telling correct?
*April 14, 2011*

**Literature**

thank you!!
*April 14, 2011*

**Literature**

I was wondering if someone could help me find information on the short story "Died and Gone to Vegas" by Tim Gautreaux. I read the story but didn't understand it to well. I was just wondering what the theme is. I tried to look it up but I cannot find any useful ...
*April 14, 2011*

**English - Native speakers**

Your toiletries are the things that you use relating to your personal hygiene and grooming. Eau de toilette is the 'perfume' with a higher percentage of water. I get where the confusion came from :) Anyway, hope this helps
*April 14, 2011*

**marketing**

Well, if you don't have a clear process of how you develop your new-product you won't be able to measure potential sucess or failure of the product, will you? One example process... Say you have employees draft their ideas (you'd say what they need to include) and ...
*April 14, 2011*

**probability and counting**

(1 pt) A box contains 25 yellow, 28 green and 38 red jelly beans. If 13 jelly beans are selected at random, what is the probability that: a) 5 are yellow? b) 5 are yellow and 7 are green? c) At least one is yellow?
*April 13, 2011*