# Posts by Laura

Total # Posts: 1,236

**math**

thank you

*September 5, 2009*

**math**

commutative property?

*September 5, 2009*

**math**

0 +16 = 16+ 0 <<< what property is this?

*September 5, 2009*

**algebra**

The sides of a triangle are in the ratio 5:12:13. What is the length of each side of the triangle if the perimeter of the triangle is 15 in?

*August 18, 2009*

**statistics**

A random sample of 10 observations has been drawn from a normal population, and the sample variance is found to be s² = 19.5. Determine the 98% confidence interval for ó².

*August 12, 2009*

**statistics**

For three independent samples, each with n= 100, the respective sample proportions are 0.30, 0.35, and 0.25. Use the 0.05 level in testing whether the three population proportions could be the same.

*August 12, 2009*

**History**

How did human history in North America differ from the events of Asia, Eurasia, and Europe before the international state of affairs? How were these differences important to the international state of affairs in 1450?

*July 31, 2009*

**11th English literature**

A letter was left off in my previous question, changing the meaning. What is the TONE of ee cummings Anyone lived in a pretty how town and Old age sticks? Examples from poems?

*June 27, 2009*

**english**

The American Experience: California Edition (Prentice Hall Literature Timeless Voices, Timeless Themes This is the textbook we are using and it says, " Satire is writing in which an author uses humor to ridicule or criticize certain individuals, institutions, types of ...

*June 25, 2009*

**english**

What is the one of e.e. cumings poems ' anyone lived in a pretty how town' and 'old age sticks'? Where is the satire? To me, satire is funny, and I don't find either of these to be funny!

*June 25, 2009*

**geometry**

how can we prove that an exterior angle of a triangle has measure equal to the sum of the measures of the 2 interior angles remote from it

*June 22, 2009*

**organic chem**

A student's correctly calculated value for the percent recovery of the purified unknown solid in a recrystallization experiment was 102%. Assume that the student performed all steps of the procedure correctly a) comment of the validity of this result; include reasons b) ...

*June 22, 2009*

**physics**

Certain neutron stars (extremely dense stars) are believed to be rotating at about 0.76 rev/s. If such a star has a radius of 10 km, what must be its minimum mass so that material on its surface remains in place during the rapid rotation? i got 3.4187*10^23 but its not right?

*June 17, 2009*

**geometry**

prove triangular inequality: if P,Q, and R are not collinear, then PQ + QR is greater than PR.

*June 11, 2009*

**Music**

I need to know the difference between rhythm, beat and pitch in the song Amazing Grace

*June 2, 2009*

**Marine Biolodgy**

you do the work yourself lola and stop being lazy and dum

*May 25, 2009*

**Chemistry**

4-methyl-2-pentyne show tautomerization ? i know tautomerization is done with a double bond but this one has a triple bond

*May 16, 2009*

**Chemistry**

4-methyl-2-pentyne show tautomerization

*May 15, 2009*

**calculus**

what's the derivative of cos3x

*May 9, 2009*

**calculus**

what is derivative of (1-2x)^-1? is it -1/(1-2x)^2 ?

*May 9, 2009*

**french exam tomorrow, WHAT DO I DO?!**

i have a french exam tomorrow and i cant remember nothing, i've looked through my book like a million times and i just forget it about 10minutes later arghhh! help?

*May 7, 2009*

**science**

Does work transfer energy as the result of motion

*April 28, 2009*

**calculus**

how do you find the limit as n approaches infinity of n/(2^n + n)?

*April 24, 2009*

**Math**

at x=4, y=0. if y=0, there is no y vlaue to "slope" the line, so the line will form vertically at x=4.

*April 24, 2009*

**COLLEGE MATH PLEASE HELP**

you need to find the permutation when order matters. look up the formula if you don't know it off hand. this should help you start...

*April 24, 2009*

**earth science**

Help please anyone? If the wet-bulb thermometer and the dry-bulb thermometer readthe same temperature, the air is said to be??? Anyone know?

*April 23, 2009*

**calculus**

how do you take a limit of [ln(1+e^n)]/2n as n goes to infinity?

*April 23, 2009*

**calculus**

determine if this converges and methods used to find its covergence or divergence. The series as n = 1 to infinity of [(2n+3)/(3n+2)]^n

*April 23, 2009*

**HCA 210 Introduction to Health Care**

According to MedicineNet(2008), “Mental illness is any disease or condition affecting the brain that influences the way a person thinks, feels, behaves and/or relates to others and to his or her surroundings. Although the symptoms of mental illness can range from mild to ...

*April 23, 2009*

**algebra**

how can i find adding,sudtracting,andmutiply fraction

*April 19, 2009*

**college math**

when eggs in a basket are removed 2,3,4,5,6 at a time there remain, respectively, 1,2,3,4,5 eggs. when they are taken out 7 at a time, none are left over. find the smallest # of eggs that could have been contained in the basket.

*April 19, 2009*

**college math**

thank you, count iblis. you have been a tremendous help with homework.

*April 19, 2009*

**college math**

what is the remainder when the sum 1^5+2^5+3^5+...99^5+100^5 is divided by 4? again a mod problem that I don't know how to work.

*April 19, 2009*

**collegemath**

find remainders when 2^50 and 41^65 are divided by 7. this is a mod problem but I don't know how to work it...

*April 19, 2009*

**number theory**

How do you prove that any palindrome, a number that reads the same backwards and forwards, with an even number of digits is divisible by 11? I know how to show a number is divisible by 11, but how do you prove the above case?

*April 19, 2009*

**number theory**

How might you go about proving that N-M is divisible by 9 when N represents an integer (such as 6923) and M represents that integer in reverse order (such as 3296)? so far, I have shown that 6923-3296=3627 is divisible by 9 by the sum of the digits, but how do you prove that ...

*April 19, 2009*

**number theory**

give an example to show that a^2 congruent to b^2 mod n need not imply that a congruent to b mod n.

*April 18, 2009*

**ecology**

I need to write an ecological profile for an animal. What exactly is an ecological profile? What does it include? Since I am not actually conducting research...it does not need abstract, materials, methods, results etc??? Please help. Thanks

*April 11, 2009*

**college math**

how would you find all prime numbers that divide 50! (factorial)?

*April 7, 2009*

**social civics**

in what way could putting a traffic on foreign shoe imports result in a disadvantage to the united states economy or united states consumers i say we would not be able to buy them

*April 7, 2009*

**Chem**

so it will be 1 as the last electron comes on that one correct? umm and i don't see the link you posted :S

*March 30, 2009*

**Chem**

what are the four quantum numbers of the last electron of As this is what i have n=4 l=1 ms= 1/2 i don't know how to calculate ml. I know it's either: -1,0,1

*March 30, 2009*

**math**

if a number is evenly divisible by 6, it is also evenly divisible by which other numbers?

*March 30, 2009*

**calculus**

thnx

*March 24, 2009*

**calculus**

what's the limit as n goes to infinity of (2 + 4/n^2)^(1/3)

*March 24, 2009*

**Physical Science**

0.83 m/s

*March 20, 2009*

**social civics**

what plan of government is used in chicago heights

*March 16, 2009*

**calculus**

what is the derivative of 4(x^2-1)^-1/2

*March 15, 2009*

**Physics**

What is the difference between an inelastic and an elastic collision? What does kinetic energy have to do with all of this? Give an explanation that explains the role of momentum, kinetic energy, and such in collisions. I think elastic collisions is when the things bounce of ...

*March 10, 2009*

**college math**

find the integral of x^2 e^-xdx with the limits of negative infinity to zero. so far, I have, lim as t approaches negative infinity of (-e^-x [x(x+2) + 2] from 0 to t does this converge or diverge?

*March 9, 2009*

**college math**

Prove: there exists x and y for c=ax+by iff gcd(a,b)/c.

*March 8, 2009*

**college math**

thanks, I'll try these methods

*March 8, 2009*

**college math**

the exact problem states: for an arbitrary integer a, verify that 3/a(2a^2+7). This is a problem out of a number theory book included in the section involving gcd.

*March 8, 2009*

**college math**

Yes, you are to prove that 3 divides [(a)(2a^2+7)] probably by using the greatest common divisor.

*March 8, 2009*

**college math**

Prove: 3/ a(2a^2 + 7)

*March 8, 2009*

**Chemistry Lab**

Hi guys, I thought it would be due to aromaticity breaking difficulty? In the bromination reaction, why are the double bonds which are par t of the phenyl r ing not brominated? A. We only added one equiv alent bromine. B. T he phenyl r ing is aromatic and aromaticity is diffic...

*March 5, 2009*

**5th grade Reading**

Its the syllable with the loudest stress. The accent is usually on the syllable before the suffixes such as ion, ical, and ity.

*March 1, 2009*

**General Question**

How does this statement go: A slim to none chance or a slim to nothing chace

*March 1, 2009*

**calc**

Using L'Hospital's Rule, find, the limit as x approaches 0 of x^(sinx)

*February 26, 2009*

**college math**

Using L'Hospital's Rule, find, the limit as x approaches 0 of x^(sinx) thank you in advance to any help.

*February 26, 2009*

**college math**

how do you take the derivative of e^(x^2)?

*February 26, 2009*

**collegte math**

Using L'Hospital's rule: find, lim as x approaches (-) infinity of xsin(1/x)

*February 26, 2009*

**Economics**

How is elasticity of supply related to elasticity of demand? Is this correct? I know that the terms supply and demand refer to the behavior of people as they interact with one another in markets. Buyers determine demand and sellers determine supply. Just as we can measure how ...

*February 26, 2009*

**Social Studies**

1. The president of the United States is elected by the electoral college. What type of system is this? 2. In ancient Athens (Greece) tribes and generals took turns at power. This is an example of what type of political system? 3.What type of political system is headed by ...

*February 26, 2009*

**Chemistry**

What is the difference between an amino acid and a protein? How does this difference in structure affect biological function?

*February 23, 2009*

**Chemistry**

State two differences between DNA and RNA.

*February 22, 2009*

**Chemistry**

Give an example of a disaccharide

*February 22, 2009*

**Chemistry**

The question is with a lab that I have already done. Here are my numbers moles of malachite in 1g 221.12 moles of CuO produced 141.57 ratio of moles of CuO produced per moles of malachite decomposed 79.55 Use the mole ratio of CuO produced per mole of malachite to write a ...

*February 22, 2009*

**Chemistry**

I need to write a balanced equation for this problem and am having difficulty doing so. The question is this: use the mole ratio of CuO produced per mole of malachite to write a balanced equation for the malachite decomposition reaction. Assume that CO2 is also a product of ...

*February 22, 2009*

**Chemistry**

I need to write a balanced equation for this problem and am having difficulty doing so. The question is this: use the mole ratio of CuO produced per mole of malachite to write a balanced equation for the malachite decomposition reaction. Assume that CO2 is also a product of ...

*February 22, 2009*

**Chemistry**

Why do carboxylic acids generally have higher melting and boiling points than alcohols, ketones, and aldehydes of comparable mass?

*February 21, 2009*

**Chemistry**

Explain why alcohols of lower molecular weight are generally soluble in water but those of higher molecular weights are generally not.

*February 21, 2009*

**college math**

How do you prove: If a/b, then a/bc So far I have: Since a/b, then b=ac where c is an integer. Now where do i go?

*February 21, 2009*

**Chemistry**

What are amine salts?

*February 18, 2009*

**Chemistry**

An alcohol has an OH functionally in it. Do you expect it to be a base? Why, or why not?

*February 18, 2009*

**Economics**

How does the government participates in a mixed economy? Based on principles of the free market, allowing some government intervention. Is there anything else i can say?

*February 18, 2009*

**college math**

how do you integrate (cos^2 x)^4

*February 15, 2009*

**college math**

thnx

*February 15, 2009*

**college math**

is the integral of 1/x^2, 2x ln of the absolute value of x^2?

*February 15, 2009*

**college math**

thank you. i understand now.

*February 15, 2009*

**college math**

how do you integrate ln(x^2+1)dx?

*February 15, 2009*

**math**

yes, I got this answer, as well THANKS

*February 15, 2009*

**math**

how do you integrate (3x+1)/(x-1)x^2 dx?

*February 15, 2009*

**math/ cal**

thank you for your answer, but this example problem is not the same as mine. the example problem is (sin (x))^2, in other words the whole quantity is squared. mine is just sin of x^2. any suggestions here?

*February 15, 2009*

**math/ cal**

how do you integrate sin (x^2) dx?

*February 15, 2009*

**Chemistry**

Name an isomer of pentane (that is not cyclic) and write down its structure.

*February 14, 2009*

**adult education**

I am currently studying for the cbest exam in all three areas, math, reading and writing. Does anyone have any current information that would help better prepare for these tests.

*February 14, 2009*

**Chemistry**

What is the three dimensional structure of methane? Why?

*February 14, 2009*

**Chemistry**

What is the difference between hydration and hydrogenation reactions?

*February 14, 2009*

**CHemistry**

Why do cis and trans isomeric compounds exhibit different properties?

*February 14, 2009*

**Chemistry**

Why is the benzene molecule represented as " a flat cyclohexane with a ring inside?"

*February 14, 2009*

**Chemistry**

Why is benzene much less reactive than 1, 3, 5-cyclohexatriene?

*February 14, 2009*

**Chemistry**

Are these compounds organic, if not what are they? Kmno4 CH3OH C6H6 PdC12 CH3CO2H

*February 14, 2009*

**Chemistry**

What is the formula of 1,3-butadiene?

*February 11, 2009*

**Chemistry**

Name one structural and one chemical difference between acetylene and ethylene. Give reasons.

*February 11, 2009*

**Chemistry**

Name an isomer of pentane (that is not cyclic) and write down its structure.

*February 11, 2009*

**Chemistry**

What is the three dimensional structure of methane? Why?

*February 11, 2009*

**Chemistry**

What causes cycloalkanes to have two less hydrogen atoms than similar alkanes that are open chain ones?

*February 11, 2009*

**Economics**

1. The main disadvantage of using shells as money, instead of coins, would be a lack of: a. durability b. portability c. uniformity d. divisibility I think its B. portability?

*February 11, 2009*

**Economics**

Thank you, for your feedback. I just read another part of my economic book and B is definitely the answer.

*February 11, 2009*