Sunday

November 29, 2015
Total # Posts: 1,628

**physics**

The diffusion coefficient for calcium ions crossing a biological membrane 10nm thick is 300 micrometers squared/second and the concentration difference of calcium ions across the membrane is 400 mol/m^2 (Molar mass of calcium is 40 kg/mol) Determine the number of moles of ...
*March 27, 2010*

**CHEMISTRY**

Hey 1)how do you estimate the line widths (full width half maximum) of the peaks arising from: (a) The emission of a hollow cathode lamp (b) The absorption peak of caffeine in the UV –visible spectrum (c) The d-d transition observed for Ni2+ in aqueous solution 2)Comment ...
*March 26, 2010*

**Physics**

4.2m
*March 23, 2010*

**Chem**

Solid carbon dioxide (dry ice) goes from solid to gas at -78C. The molar heat of sublimation is 25.3 kj/mol. In one experiment 34.5g of dry ice are placed in an insulated isolated container with 500 g of water at 25C. What temp of the water is expected after all bubbles are ...
*March 11, 2010*

**Time Zones**

Check my work. Calculate the correct time in brackets: 1. 1:00am at 30W = (11:00pm) at 60W 2. 3:00pm at 15W = (1:00pm) at 45W 3. 1:00pm at 120E = (9:00am) at 60E 4. 12:00pm at 15E = (6:00pm) at 105E 5. 11:00am at 15E = (9:00am) at 15W Calculate the correct longitude in ...
*March 4, 2010*

**Physics**

got it v=[(2*m1)/(m1+m2)]Vo then take your answer and insert into 1/2mv^2 and divide by 1000
*March 3, 2010*

**Physics**

i agree with that but how would you find the kinetic energy acquired by the nail after you get these numbers?
*March 3, 2010*

**chemistry**

Reacting 959 mol of SiO2 with excess carbon yields 28.8 kg of SiC. What is the percentage yield? SiO2 + 3C--> SiC + 2 CO
*March 2, 2010*

**chemistry**

2 KClO3(s)--> 2 KCl(s) + 3 O2(g) How many milliliters of O2 will form at STP from 38.8 g KClO3?
*March 2, 2010*

**math**

the ratio of single screen theaters to multiple screen theaters is 1 to 15. if there are 9 single screen theaters, how many multiple screen theaters are there?
*March 1, 2010*

**chemistry**

10.0mL of solution containing 20.0 mL of 1.0 M NaX (unknown base) and 10.0 mL of 1.0 M HX (unknown acid) was diluted with 50.0 ml water. The pH is 4.92. What is the concentration of HX after dilution and X- after dilution? What is the equilibrium concentration of HX, X-, and ...
*February 27, 2010*

**chemistry**

calculate number of grams of iron in one mole of ferrous ammonium sulfate.hint how many moles are in one mole of ferrous ammonuim sulfate?
*February 26, 2010*

**biology honors**

Summarize Griffith's transformation experiments
*February 23, 2010*

**Environmental Science**

After spraying crops with ddt for several years, farmers found that population of insects pests rebounded. suggest another reason based on what you know about population food pyramid predators and competitors
*February 23, 2010*

**chemistry**

Write the condensed structure for Methylpropyl ether Would it be C4H11O? CH3-O-CH3CH2CH3
*February 22, 2010*

**Accounting**

dadfadf
*February 22, 2010*

**chemistry**

When 0.767 g of Ca metal is added to 200.0 mL of 0.500 M HCl(aq), a temperature increase of 125C is observed. Assume the solution's final volume is 200.0 mL, the density is 1.00 g/mL, and the heat capacity is 4.184 J/gC. (Note: Pay attention to significant figures. Do not ...
*February 21, 2010*

**Physics**

A student presses a book between his hands, as the drawing indicates. The forces that he exerts on the front and back covers of the book are perpendicular to the book and are horizontal. The book weighs 32 N. The coefficient of static friction between his hands and the book is...
*February 15, 2010*

**Math**

In the following table R(t) is the quarterly revenue for an international tortilla producer t quarters after December 1999. Use the table to answer the following questions. Find R(t) where t=4. What was the revenue 2 quarters after 1999.. What does t equal when R(t) = 486. (In...
*February 14, 2010*

**Trig**

How do you express these problems as single trigonometric function values or as single numbers, using identities? 1. cos^2pi/8-1/2 2. tan34degrees/2(1-tan^2 34degrees) 3. 1/8sin29.5degreescos29.5degrees
*February 14, 2010*

**college**

In the following table R(t) is the quarterly revenue for an international tortilla producer t quarters after December 1999. Use the table to answer the following questions. Find R(t) where t=4. What was the revenue 2 quarters after 1999.. What does t equal when R(t) = 486. (In...
*February 14, 2010*

**English**

9) I have two hours of PE a week, but I have three hours of French a week. Instead of doing normal training, we practice golf. How many hours of French do you have a week?
*February 14, 2010*

**Science- Meteorology**

Most climate models show that the poles will warm faster than the tropics. What effect will this have on winter storms in the mid-latitudes?
*February 10, 2010*

**Math**

1+2+3+4=10 plants
*February 10, 2010*

**begining algebra**

side 1= 3x side 2= x side 3= x+7 3x + x + x+7 = 62 5x = 55 x=11 side 1= 3(11) = 33 side 2= (11) = 11 side 3= (11)+7 = 18
*February 10, 2010*

**Physics**

The punter on a football team tries to kick a football so that it stays in the air for a long "hang time." If the ball is kicked with an initial velocity of 25.0 m/s at an angle of 57.5° above the ground, what is the "hang time"?
*February 7, 2010*

**calculus**

An airplane is flying on a bearing of 80 degrees at 540mph. A wind is blowing with a bearing of 100 degrees at 55mph. Find the component form of the velocity of the airplane.
*February 7, 2010*

**Math**

The function H described by H(x)= 2.75x + 71.48 can be used to predict the height, in centimeters, of a woman whose humerus( the bone from the elbow to the shoulder) is x cm long? Predict the height of a woman whose humerus is 35 cm long. Is this correct? 2.75(35) + 71.48= 167...
*January 31, 2010*

**Math**

80% of what number is 20? Would this be 100?
*January 31, 2010*

**physics**

x=1/2(vo+v)t
*January 31, 2010*

**physics**

vo1=a1t1
*January 31, 2010*

**algebra 1**

marcy has a total of 100 dimes and quarters. if the total value of the coins is $14.05, how many quarters does she have?
*January 31, 2010*

**algebra 1**

marcy has a total of 100 dimes and quarters. if the total value of the coins is $14.05, how many quarters does she have?
*January 31, 2010*

**Math**

The digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 are repeated in such a way that when the digits repeat the greatest digit is removed: what is the 1111st number in the pattern ex:...
*January 20, 2010*

**Math-Fractions**

that's cool. Thanks
*January 19, 2010*

**Math-Fractions**

I'd like to learn this. How did you get 15/8. Did you multiply 5 by 3 to get that?
*January 19, 2010*

**Rip Van Winkle**

1.What did the story implies? (in history) 2.Why the author discuss about the relationship between England and America through the relationship between Rip and his wife?
*January 16, 2010*

**Thomas Paine**

The cause of America is in a great measure the cause of all mankind. Many circumstances hath, and will arise, which are not local, but universal, and through which the principles of all Lovers of Mankind are affected, and in the Event of which, their Affections are interested...
*January 16, 2010*

**american literature**

Why is Thomas Paine the Spokesmen of American Revolution?
*January 16, 2010*

**literary**

American Lit how did Jonathan Edwards balance his idea and his religion?
*January 16, 2010*

**American Lit**

how did Jonathan Edwards balance his idea and his religion?
*January 16, 2010*

**math**

21=3(t-3)+3t
*January 14, 2010*

**Algebra**

Find the sum of the first four terms of the geometric sequence with a = -3 and r = 3. I have NO idea how to attempt to solve this. I do not want an answer just instuctions. Thanks
*January 11, 2010*

**statistics**

Oh yeah, I forgot about that! Per person definitely puts it in a more personal perspective. I just wasn't sure if this question is looking for a more common sense or mathematical answer.
*January 10, 2010*

**statistics**

Is it also because it may vary exactly how many million people live in a country, so taking the average per person is a lot easier to compare than average per country?
*January 10, 2010*

**statistics**

Burning fuels in power plants or motor vehicles emit carbon dioxide, which contributes to global warming. Table 1.3 displays CO2 emissions per person from countries with populations of at least 20 mil. Why do you think we choose to measure emissions per person rather than CO2 ...
*January 10, 2010*

**9th grade**

I'm doing this word search for my 9th grade honors physical science class, and i don't understand one thing. it says 'blue, striped and round are examples of this' when we're talking about matter and phases of matter and density/mass/weight/volume. stuff ...
*January 6, 2010*

**Alberbra**

Please help with graphing a quadratic function. y=(x-1)^2 Got stuck at y=(x-1)(x-1) and p=1, q=1 Which doesn't work, because you can't fix a vertex with one point on a graph.
*January 1, 2010*

**social studies**

1.For one day, keep track of what you do from the time you get up until the time you go to bed. For each hour, record one of these activities: *work *play *school *recreation *other I've made my chart, but I need help on the second part which is: 2.Make a circle graph that...
*December 21, 2009*

**psychology**

Evaluations of a particular belief, person, object, or idea describe a person’s: attitudes motivation predispositions biases
*December 21, 2009*

**Ethics**

I am suppose to write an essay on a Moral Issue of my choice, but I do not really remember all of the Moral Issues, can someone give me a hand on the best one to write on, I need a awesome grade. Thanks Kelly
*December 15, 2009*

**English**

What does it mean when an author uses a chronological and necessarily episodic structure to keep their main character at the center of all action.
*December 12, 2009*

**English**

What is a fictionalized autobiography and a vernacular?
*December 12, 2009*

**physics**

Yeah I know it is! But it's really confusing me and it's what my teacher wants. Say I was to pick a height of 25m and a Velocity of 20.0m/s, what would be my next step?
*December 11, 2009*

**physics**

How can you solve for that problem, by using another approach?
*December 11, 2009*

**physics**

Three identical balls are thrown from a cliff of height, h, above a horizontal plane. One ball is thrown at an angle of 45 degrees above the horizon, the second is thrown horizontally, and the third is thrown at an angle of 30 degrees below the horizon (so, part of this ...
*December 11, 2009*

**physics**

If a ball is thrown off a 17.9m roof with the velocity of 23.9m/s and it takes 1.91sec to reach the ground, What is the horizontal displacement and the Velocity right before it hits the ground?
*December 11, 2009*

**physics**

While on a trail, a mountain biker encounters a sandy patch that is 7.1 m long. The speed of the bike entering the patch is 10.1 m/s. If the force exerted by the sand on the bike/biker system (103.8 kg) is 514 N, determine the speed of the biker when exiting the sandy patch.
*December 10, 2009*

**2nd grade**

Nope! Cartoon... the a is short C-A-R the A is short Otherwise it would say it's name like B-A-K-E The O is short to! OOOO You want it to say it's name for it to be a lONG vowel. Like the word O-A-T
*December 8, 2009*

**physics**

Two masses are attached to an Atwood machine. the mass of block A is 12.3kg and the mass of B is 4.2kg. the pulley is massless but has kinetic friction of 16N. The blocks are released from rest, what is the acceleration of the system
*December 4, 2009*

**physics**

The two blocks in the figureoscillate on a frictionless surface with a period of 1.7s . The upper block just begins to slip when the amplitude is increased to 34cm . What is the coefficient of static friction between the two blocks?
*December 2, 2009*

**English**

Can someone please check the grammar in these last two for me. I posted this about 8:00 and no one ever answered. I do understand that you are helping other individuals to. Your help is greatly appreciated. The tension that Irene has towards Bellew shows that she does not ...
*December 1, 2009*

**English**

Sorry can you please check the grammar.
*December 1, 2009*

**English**

Can you please check these last two for me. Thank You and have a great evening. The tension that Irene has towards Bellew shows that she does not appreciate the fact that he is an racist individual, who does not take other people's feelings into perspective when he talks. ...
*December 1, 2009*

**English**

Can you please check the grammar in these two separate points. Thank you. Irene shares with Clare how her daughter would be affected if John found out about his own wifes “true race” and reveals to Clare would could happen. The lesson that Larson is trying to teach ...
*December 1, 2009*

**physics**

The amplitude of an oscillator decreases to 69.0% of its initial value in 15.5s. a) What is the value of the time constant?
*December 1, 2009*

**English**

Can you please just check the grammar in this for me. Larsen's theme goes to prove that when somebody is unable to recognize their real identity, their false face that they put on leads them towards possible danger. Those individuals are willing to risk the good things ...
*December 1, 2009*

**physics**

is Me the mass of the earth? and re the radius of the earth?
*December 1, 2009*

**physics**

A rocket is launched straight up from the earth's surface at a speed of 1.80×104 m/s^2. a)What is its speed when it is very far away from the earth?
*December 1, 2009*

**physics**

Planet Z is 1.00×10^4 km in diameter. The free-fall acceleration on Planet Z is 10.0 m/s^2. a)What is the mass of Planet Z? b)What is the free-fall acceleration 9000 km above Planet Z's north pole?
*December 1, 2009*

**physics**

A sensitive gravimeter at a mountian observatory finds that the free-fall acceleration is 6.00 X 10^3 m/s^2 less than that at sea level. What is the observatory's altitude?
*December 1, 2009*

**government**

Whatis the historical explanation of the 7th amendment?
*November 30, 2009*

**Statistics**

Private colleges and universities rely on money contributed by individuals and corporations for their operating expenses. Much of this money is put into a fund called an endowment, and the college spends only the interest earned by the fund. A recent survey of eight private ...
*November 28, 2009*

**chemistry**

45kj/mol
*November 15, 2009*

**World Liturature**

Explain the significance of the title Quality by John Galsworthy
*November 15, 2009*

**English Lit**

thank you^^
*November 14, 2009*

**English Lit**

Analysis the double voice in Anne Bradstreet's poem....."The Prologe" "The Author to Her Book"
*November 14, 2009*

**English Lit**

The double voice in Anne Bradstreets's poem.
*November 14, 2009*

**English Lit**

The double voice writer in 18th century of American Lit. And the double voice is...?
*November 14, 2009*

**English Lit**

What's the Puritan Thought in Mary Rowlandson, ¡§A Narrative of the Captivity and Restoration of Mrs. Mary Rowlandson¡¨?
*November 14, 2009*

**English Lit**

What's the Ideological conflict in the eighteenth century of United States?
*November 14, 2009*

**Chemistry**

If a movie has 0.16 hour remaining, how many seconds of movie remain?
*November 11, 2009*

**1st grade**

Hello there, A map can help you by showing you the exact location of something. By having road names, rivers, mountians and more! I hope this helped! -Kelly
*November 10, 2009*

**Physics**

A golf club 1.01 m long completes a downswing in 0.25 s through a range of 180°. Assume a uniform (constant) angular velocity, what is the average angular velocity of the club? I don't even know what equation to begin with.
*November 3, 2009*

**Statistics**

Suppose that the probability distribution of a random variable x can be described by the formula P(x) = x/15 For each of the values x = 1, 2, 3, 4, and 5. For examples, then, p(x=2) = p(2) = 2/15 a Write out the probability distribution of x. b Show that the probability ...
*October 26, 2009*

**History**

I have to write and essay on A Country Divided, describing the evolution of events that divided America and led to succession, and include various efforts of compromise?? I have no idea were to fined anything on the subject, can someone help me out with were to look? Thanks Kelly
*October 23, 2009*

**Math**

Thank you both!
*October 21, 2009*

**Math**

Write the numeral in base ten. 7001eight.
*October 21, 2009*

**Math**

The verticle circles are below the middle horizontal circle.
*October 21, 2009*

**Math**

Yes, they look like that. Does that change the sequence?
*October 21, 2009*

**Math**

Use each of the numbers 7, 8, 9, 10, and 11 once and only once to fill in the circles so that the sum of the numbers in the three horizontal circles equals the sum of the numbers in the three vertical circles. Of the three possible solutions, which numbers can be used in the ...
*October 21, 2009*

**Math**

Yes, that is what I got. Thank you!
*October 21, 2009*

**Math**

Thought so, just wanted to check. Thank you.
*October 21, 2009*

**Math**

What percent of students in the college are history majors (to the nearest tenth of a percent)? 200 students major in math 300 students major in history 400 major in english 150 major in science 175 major in other Total number of students divided by the number of math majors?
*October 21, 2009*

**Math**

Where are you getting your fractions from? Are you doing 2 yellow cars over 4 tan cars?
*October 21, 2009*

**Math**

The bar graph below shows the numbers of various colors of cars owned by the employees of a certain business. Write five ratios (expressed as fractions in lowest terms) that compare the least popular color to each of the other colors. There are: 2 yellow cars 4 tan cars 6 ...
*October 21, 2009*

**Math**

Oh okay. I see. Thank you!
*October 21, 2009*

**Math**

Write the percent as a fraction in the lowest terms. 0.05% Would it be 1/20?
*October 21, 2009*

**Math Word Problem**

Oh I had it backwards, thank you Reiny for your help with all my questions.
*October 21, 2009*

**Math Word Problem**

Sales of frozen pizza for a club fund-raiser increased from 500 one year to 575 the next year. What was the percent of increase? Would I divide 500 by 75?
*October 21, 2009*