Wednesday

March 1, 2017
Total # Posts: 858

**Biology**

Humans have about 20,000 genes in our genome. Explain how cells differentiate into different kinds of cells even though they have the same set of 20,000 genes in their nuclei, so they are genetically identical.

*April 12, 2013*

**Maths**

its wrong steve

*March 19, 2013*

**Chemistry**

nevermind i got it

*March 16, 2013*

**Chemistry**

Hydrocinnamoyl chloride + AlCl3 --> ??

*March 16, 2013*

**Chemistry Equilibrium**

Which of the following conditions is always true at equilibrium? deltaG=0, Q=1, K=1, deltaG=deltaG(standard), deltaG(standard)=0, Q=0, deltaG(standard)=1 I'm so confused, please help!

*March 14, 2013*

**~*Math Probability*~**

Which expression would you use to figure out the number of ways you can arrange the letters in the word equation? (1 point) 8! 8P4 4P8 4! Five friends are having their picture taken. How many ways can the photographer arrange the friends in a row? (1 point) 150 100 120 80 How ...

*March 13, 2013*

**Calculus**

How would I solve the limit for this sequence. [n^(2)]*[1-cos(2.4/n)] I used L'Hopital's rule by putting n^(-2) in the bottom, but I got the wrong answer of -1.44 in the end. Please help, thanks!

*March 8, 2013*

**Chem Problem**

Nevermind, I figured it out!

*March 1, 2013*

**Chem Problem**

I need help solving this question, I have no idea what I'm supposed to do. What is the minimum pressure in kPa that must be applied at 25 °C to obtain pure water by reverse osmosis from water that is 0.165 M in sodium chloride and 0.029 M in magnesium sulfate? Assume ...

*March 1, 2013*

**Chem Problem**

I need help solving this question, I have no idea what I'm supposed to do. What is the minimum pressure in kPa that must be applied at 25 °C to obtain pure water by reverse osmosis from water that is 0.165 M in sodium chloride and 0.029 M in magnesium sulfate? Assume ...

*March 1, 2013*

**Language Arts**

That's what I thought too, but what if you only had to select one? Which one is more of a fact?

*February 28, 2013*

**Language Arts**

What fact does the author use to support her opinion about bleach? (1 point) 1. Bleach is a poison. 2. Bleach is an expensive part of processing water. 3. Bleach isn’t terrific to have around. __________________________________________ Note: This is not a question about ...

*February 28, 2013*

**Organic Chemistry**

thank you!!

*February 22, 2013*

**Organic Chemistry**

NMR: What can be said about proton spin decoupling? a) It depends on the number of attached protons. b) It slows the deshielding effects of π -electron circulation. c) It is the same as Distortionless Enhancement with Polarization Transfer. d) It is an instrumental ...

*February 22, 2013*

**ALGEBRA**

use the pythagorean theorem to find b when a=14 and c=y (triangle) b=

*February 17, 2013*

**ALGEBRA 2**

the airline cost for x thousand passengers to travel round trip from nyc to atlanta is given by C(x)= radical 0.3x+1 where C(x) is measured in millions of dollars and x> 0. find the airline's cost for 15,000 passengers (x=15) to travel from new york to atlanta. round ...

*February 17, 2013*

**ALGEBRA 2**

the airline cost for x thousand passengers to travel round trip from nyc to atlanta is given by C(x)= radical 0.3x+1 where C(x) is measured in millions of dollars and x> 0. find the airline's cost for 15,000 passengers (x=15) to travel from new york to atlanta. round ...

*February 17, 2013*

**algebra**

5 radical 5 and 9 radical 5 ____like radicals. a. are b. are not

*February 15, 2013*

**algebra**

the length of a rectangular photograph is 5in. more than the width. If the area is 50 in^2 what are the dimensions of the photograph? the width is__in. and the length is ____in.

*February 15, 2013*

**Chemistry**

How much energy as heat is removed from the hand when 5.00 grams of Ga initially at 20 degrees C melts? The value of Heat Fusion is 5.576 kJ-mol and the specific heat of Ga is 0.374 J-g-K. Take the final temp to be 29.76 degrees C.

*February 8, 2013*

**Chemistry**

How much energy as heat is removed from the hand when 5.00 grams of Ga initially at 20 degrees C melts? The value of Heat Fusion is 5.576 kJ-mol and the specific heat of Ga is 0.374 J-g-K. Take the final temp to be 29.76 degrees C.

*February 7, 2013*

**Physics**

A 69990 kg locomotive is traveling at 9.86 m/s when its engine and brakes both fail. How far will the locomotive roll before it comes to a stop? (The coefficient of rolling friction is 0.002.)

*January 22, 2013*

**English**

I can't find anything wrong. I know that an author isn't listed, but I don't see an example of how to properly cite with no author.

*January 22, 2013*

**English**

Is the below the correct way to cite an artical from a website in APA? I got marked off on my assignment for having it this way. Researchers at national institute of technology release new data on ethanol. (2013, Jan 18). Drug Week. Retrieved from (website URL)

*January 22, 2013*

**Physics**

A sailor climbs to the top of the mast, 12.55 m above the deck, to look for land while his ship moves steadily forward through calm waters at 4.63 m/s. Unfortunately, he drops his spyglass to the deck below. Where does it land with respect to the base of the mast below him?

*January 21, 2013*

**Physics**

A ball thrown horizontally at 22.76 m/s travels a horizontal distance of 46.81 m before hitting the ground. From what height was the ball thrown?

*January 21, 2013*

**English**

Thanks so much I was worried I would get hate posts you rock!!!!

*January 10, 2013*

**English**

HI, I need help on a question I have read both books 50 times now what is the difference between Barrio boy and no gumption please help. And if your going to hate please don't state thanks!!!!

*January 10, 2013*

**APUSH**

Please help! What event made the ratification of the Treaty of Versailles virtually impossible? a. The fact that Wilson had not taken any representatives from the opposition to France b. Wilson's open contempt for the opposition in the Senate c. Wilson's tactics of ...

*December 28, 2012*

**APUSH**

Race relations were _____ during World War 1: a. improved thanks to the efforts of government programs b. had moments of violence, but predominately improved material wealth for blacks in the north c.were among Wilson's top priorities; he had strong relations with W. E. B...

*December 26, 2012*

**SUPER SUPER SUPER NEED OF HELP**

What is the name of money is used in Haiti? What does the word? Why are there windows and portals on European banknotes? Look at all the countries whose money is straightforward. What they have in common? Is that the Canadian dollar has the same value as the U.S. dollar? I ...

*December 16, 2012*

**chemistry**

but answer is not right its not 5.00*10^22

*December 14, 2012*

**chemistry**

Chemical analysis of a silicon crystal reveals gallium at a level of 3.091×10−8 atomic percent. Assuming that the concentration of thermally excited charge carriers from the Si matrix is negligible, what is the density of free charge carriers (free carriers/cm3) in ...

*December 14, 2012*

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.35 kg m-3. Under these conditions the total surface area of the balloon is 0.57 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

*December 14, 2012*

**chemistry**

You wish to increase the carbon content of a slab of steel by exposing it to a carburizing atmosphere at elevated temperature. The carbon concentration in the steel before carburization is 165.0 ppm and is initially uniform through the thickness of the steel. The atmosphere of...

*December 14, 2012*

**CHEMISTRY**

i cant get right answer pls help

*December 14, 2012*

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

*December 14, 2012*

**chemistry**

The diffusion coefficient of silver (Ag) in copper (Cu) has the following values: T (K) D (m2s-1) 923 5.42 x 10-16 1173 1.34 x 10-13 (a) Calculate the activation energy for diffusion of silver in copper. Express your answer in units of J/mol.

*December 14, 2012*

**chemistry**

A latex balloon, wall thickness 3.091 x 10-4 m, contains helium at a concentration of 0.5 kg m-3. Under these conditions the total surface area of the balloon is 0.72 m2. The diffusion coefficient of He in latex at room temperature is 4.9 x 10-9 m2s-1. Calculate the rate of ...

*December 14, 2012*

**chemistry**

(a) Cadmium telluride (CdTe) is a semiconductor witha band gap, Eg, of 1.45 eV. Calculate the value of the absorption edge of this material. Express your answer in meters.

*December 14, 2012*

**algebra**

X^2 x+15 ----- * ------ = X^2+7 x

*December 9, 2012*

**algebra**

X^2 * x+15 X^2+7 x

*December 9, 2012*

**chemistry**

All you do is just write out the equation onto the product side. B. NaNO3(s)→Na^+(aq)+NO3^−(aq) C. FeCl3(s)→Fe3^+(aq)+3Cl^−(aq) The same for D. You're Very Welcome!

*November 23, 2012*

**Physics**

Twice as massive.

*November 13, 2012*

**Chemistry**

the answer for b above is totally wrong, >= 3.

*October 29, 2012*

**Math**

$10

*October 24, 2012*

**physics**

7.09 m/s

*October 21, 2012*

**english**

Your Answer B. Figure of speech MY RESOURCE - 100% graded assignment JUST REMEMBER IT IS IMPORTANT TO UNDERSTAND WHY THAT ANSWER IS CORRECT. Look at definitions closely

*October 16, 2012*

**precal**

A pile driver pounds a steel column into the ground. On the first drive, the column is pounded 1.65 metres into the ground, and on each successive drive it moves 80% as far as it did on the previous drive. The least number of drives required to drive the column a total of 8.2 ...

*October 14, 2012*

**Dynamics**

Fricken Jeff... Stuck on this one, too. Screw this homework!

*September 23, 2012*

**chemistry help!**

Potassium nitrate has a lattice energy of -163.8 kcal/mol and a heat of hydration of -155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 105 kJ of heat?

*September 19, 2012*

**AP Calc**

What are the zeros (roots) of the function 2x/((x^2)-1) ? Would it just be (0,0)? Thanks in advance!

*September 13, 2012*

**calculus**

The point P(4, −2)lies on the curve y = 2/(3 − x). (a) If Q is the point(x, 2/(3 − x)),use your calculator to find the slope mPQ of the secant line PQ (correct to six decimal places) for the following values of x. 1) 3.9 mPQ= 2) 3.99 mPQ= 3)3.999 mPQ= 4) 4.1 ...

*August 28, 2012*

**chem**

no question - just thank you "drbob", you've answered a few of my questions.

*July 14, 2012*

**CALCULUS!**

When S is sales and t is time, and the original function is S(t), what does S'(24)>0 and S''(24)<0 represent?

*May 24, 2012*

**CALCULUS!**

When S is sales and t is time, and the original function is S(t), what does S'(24) and S''(24) represent?

*May 24, 2012*

**Calculus PLZ HELP!**

What is the limit as x approaches infinity of a constant? Is it the constant or zero? Thanks in advance!

*May 24, 2012*

**Everything**

Ms.Sue is 9/10 a possible teacher. As a teacher she could probably tell that this student doesn't need any help with the work. Just wanted the answers not any help. There are teachers on this site you know. If these students keep up this cheating this site could get ...

*May 8, 2012*

**HISTORY PLEASE HELP!**

I think the answer is B. Is that correct?

*April 17, 2012*

**HISTORY PLEASE HELP!**

The earliest and most enthusiastic proponents of Manifest Destiny were: A. Investment Bankers B. Eastern Politicians C. Northeast Industrialists D. Southern Proslavery Advocates E. Protestant missionary groups

*April 17, 2012*

**HISTORY**

The minister sent to Mexico in 1845 had strict orders to accomplish what as his primary goal? A. Secure Mexican approval of the annexation of Texas B. Purchase California for $25 million C. Get Mexico to grant their claims to Oregon to the US D. Settle the $3 million in claims...

*April 15, 2012*

**physics**

Whoever posted the answer to this problem is a moron. Yes, the launch angle in the horizontal direction is 45, but that is not the equation for the Max vertical distance.

*April 1, 2012*

**chemistry**

A certain first order reaction has a rate constant of 3.75x10^-2 s^-1 at 25.0C. What is the value of k at 70.0C when the activation energy is 135 kj/mol? Would I use the formula K=Ae ^-Ea/RT even though I have two temperatures?

*March 14, 2012*

**CHEM HELP!**

Thank you for taking the time to answer me on this. I used the gaw law to solve for NH3 for the mass of it to then add it to the mass of H2S to find NH4HS. I think Im still a little confused on how to go about this, but hopefully by your answer I can figure it out.

*March 12, 2012*

**CHEM HELP!**

I plugged in the values P is pressure I have for NH3 which is 2.78, 5L for V, n, R the gas constant and T 298K. to get .5684 mol to .03388 g of NH3

*March 12, 2012*

**CHEM HELP!**

after using the ideal gas law to find moles then mass of NH3 to add to the H2S I got a answer of 3.0334g This is my last attempt to enter in a answer for the program I am using and I don't want to lose points, obviously. I just want to see if anyone can check to make sure ...

*March 12, 2012*

**CHEM HELP!**

NH4HS<-->NH3+H2S What is the minimum mass of NH4HS that must be added to the 5.00-L flask when charged with the 0.300g of pure H2S, at 25C to achieve equilibrium?? Kp=.120 at 25C initial pressure of H2S in flask = .0431atm partial pressures of H2S and NH3 .326, .369 mole...

*March 12, 2012*

**Calculus (Intermediate Value Theorem)**

If f(x)= x^3-x+3 and if c is the only real number such that f(c)=0, then c is between ______?

*March 12, 2012*

**chemistry help!!!!!**

so this set up would be 1.6= (1-p)^2/p which then turns to p^2+1.6p-1 then solve the quadratic equation?

*March 11, 2012*

**chemistry help!!!!!**

Oops! I thought that was there. It is A(g)<-> 2B(g)

*March 11, 2012*

**chemistry help!!!!!**

Consider the following reaction: Find the equilibrium partial pressures of A and B for each of the following different values of Kp. Assume that the initial partial pressure of B in each case is 1.0 atm, and that the initial partial pressure of A is 0.0 atm. Make any ...

*March 11, 2012*

**chemistry**

could you please explain the last question, c, again. Ive tried a few times but I am still getting it wrong.

*March 11, 2012*

**chemistry**

Ah! Yes that worked out perfectly! Thank you so much for the help. That one really had me stuck!

*March 11, 2012*

**chemistry**

Oh okay that makes more sense now. Thank you for clearing that up. I tried entering in 2.78 for my partial pressure of NH3 but the program I am using is telling me that is incorrect?

*March 11, 2012*

**business**

outline the role team work or team building can play in the business planning process?

*March 11, 2012*

**Finance**

$4,000.08 4,200 * .9524 = 4,000.08

*March 7, 2012*

**Probability**

Thank you for the explanation MathMate! Would the answer to this question be A? Darby guesses the answers to six questions on the math portion of her college entrance exam. Each question is a true or false question. What is the approximate probability that at least 4 of her ...

*March 4, 2012*

**Probability**

Darby guesses the answers to six questions on the math portion of her college entrance exam. Each question is a true or false question. What is the approximate probability that at least 4 of her answers are correct? A. 0.23 B. 0.34 C. 0.66 D. 0.78 Explanation please??

*March 4, 2012*

**Probability**

How did you get this? = 6C4 (½)^4 (½)^2 + 6C5 (½)^5 (½)^1 + 6C6 (½)^6 (½)^0

*March 4, 2012*

**Probability**

Darby guesses the answers to six questions on the math portion of her college entrance exam. Each question is a true or false question. What is the approximate probability that at least 4 of her answers are correct? A. 0.23 B. 0.34 C. 0.66 D. 0.78

*March 4, 2012*

**Math**

Darby guesses the answers to six questions on the math portion of her college entrance exam. Each question is a true or false question. What is the approximate probability that at least 4 of her answers are correct? A. 0.23 B. 0.34 C. 0.66 D. 0.78 Is it B?

*March 3, 2012*

**Calculus**

Thank you!

*February 28, 2012*

**Calculus**

(tanx)^2 cannot be simplified to sinx/cosx because it's squared

*February 28, 2012*

**Calculus**

What is the limit as x approaches 0 of [(tanx)^2]/x?

*February 28, 2012*

**Calculus**

What is the limit as x approaches 0 of [(tanx)^2]/x?

*February 28, 2012*

**Chemistry Help PLEASE!!**

Got it! Thank you :)

*February 24, 2012*

**Chemistry Help PLEASE!!**

I think I realized what my mistake was, I assumed the reaction would go to the right, doesn't it go to the left?

*February 24, 2012*

**Chemistry Help PLEASE!!**

I don't know how to do this question, I understand we have to use ICE but I keep getting the wrong answer when I solve for x, it's just not working for me. Consider the following reaction: A(g) -> 2B (g) Find the equilibrium partial pressures of A and B for each of ...

*February 24, 2012*

**Physics**

Any assistance explaining how to work this would be great! The force exerted by the wind on the sails of a sailboat is Fsail = 480 N north. The water exerts a force of Fkeel = 240 N east. If the boat (including its crew) has a mass of 350 kg, what are the magnitude and ...

*February 24, 2012*

**history**

I think it is C or D. But I'm leaning towards C.

*February 14, 2012*

**history**

All of the following statements regarding the Monroe Doctrine are correct EXCEPT? A. Issued by Monroe in response to an onslaught by European monarchies against democracy in the Americas. B. Would have been ineffective without the backing of the British navy. C. Monroe saw ...

*February 14, 2012*

**algebra**

Yes you're right. THANK YOU SO MUCH!!

*February 13, 2012*

**algebra**

Wouldn't they both be > or = to?

*February 13, 2012*

**algebra**

Find the interval (or intervals) on which the given expression is defined: (x^2-7x+12)^(1/2)

*February 13, 2012*

**chemistry**

yes i believe e is true

*February 13, 2012*

**chemistry**

You react chemical A with chemical B to make one product. It takes 100 grams of chemical A to react completely with 20 grams of chemical B. What is true about the chemical properties of the product? a. the properties are more like those of chemical A b. the properties are more...

*February 13, 2012*

**Physics**

0.7 is the answers

*January 31, 2012*

**chemistry**

Calculate the number of moles of each ion in 10.5 mL of 0.205 M cadmium phosphate solution.

*January 22, 2012*

**chemistry**

What mass of water must be added to 0.5 mol of glucose to make a solution of 25 percent by mass?The molar mass of glucose is 180 g/mol.

*January 22, 2012*

**chemistry**

Find the formula for the compound that contains 72.4% iron and 27.6% oxygen.

*January 22, 2012*