Thursday
May 5, 2016

# Posts by christina

Total # Posts: 903

Physics
At the time this problem was written, the price of gold was \$427 per ounce, while that of platinum was \$866 an ounce. The "ounce" in this case is the troy ounce, which is equal to 31.1035 g. The density of gold is 19.3 g/cm^3 and that of platinum is 21.4 g/cm^3. a)If...
November 29, 2007

Physics
It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.20 m). As one goes deeper and deeper in the ocean, the pressure increases by 1.0*10^4 Pa for every meter below the surface. If a diver goes down 33.0 m (a bit over 100 ft) in the ...
November 14, 2007

Physics
In the Grimms' fairy tale Rapunzel, she lets down her golden hair to a length of 20.0 yards (we'll use 20.0 m, which is not much different) so that the prince can climb up to her room. Human hair has a Young's modulus of about 490 MPa, and we can assume that ...
November 14, 2007

Physics
I did that and I'm still getting a wrong answer... Is it possible that my calculations are wrong somewhere else?? I'm at a loss...
November 14, 2007

Physics
It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.20 GPa). As one goes deeper and deeper in the ocean, the pressure increases by 1.0*10^4 Pa for every meter below the surface. If a diver goes down 33.0 m (a bit over 100 ft) in the ...
November 14, 2007

Physics
I'm still getting A wrong.... F=(1.474*10^9)(7.81*10^-5)/(.25) *.0125 =5755.95 Pa
November 13, 2007

Physics
The Achilles tendon, which connects the calf muscles to the heel, is the thickest and strongest tendon in the body. In extreme activities, such as sprinting, it can be subjected to forces as high as 13.0 times a person's weight. According to one set of experiments, the ...
November 13, 2007

math
Find the surface area of the right prism. The height is 2.5 cm, the lenght is 8 cm, and the width is 5.3 cm. This is confusing. I need help.
November 11, 2007

Physics
The outstretched hands and arms of a figure skater preparing for a spin can be considered a slender rod pivoting about an axis through its center. When the skater's hands and arms are brought in and wrapped around his body to execute the spin, the hands and arms can be ...
November 7, 2007

Physics
I'm on the change in KE part and this is what I get: KEf=(1/2)(2.5*10^-2)(.150*7)^2 =.01378125 KEi=(1/2)(2.5*10^-2)(.300*1.75)^2 =.0034453125 I'm not quite sure what to do with these two numbers... I subtracted KEi from KEf, but was told I had "rounding error"...
November 7, 2007

Physics
A small block on a frictionless horizontal surface has a mass of 2.50×10−2 Kg. It is attached to a massless cord passing through a hole in the surface. The block is originally revolving at a distance of 0.300 m from the hole with an angular speed of 1.75 rad/s. The...
November 7, 2007

English
what is the indirect object in this sentence "Chandler gave her the magazine"
November 6, 2007

Physics
To strengthen his arm and chest muscles, an 83.0 kg athlete 2.00 m tall is doing a series of push-ups. His center of mass is 1.15 m from the bottom of his feet, and the centers of his palms are 30.0 cm from the top of his head. Find the force that the floor exerts on each of ...
November 5, 2007

Physics
I can't seem to find where I've gone wrong... Volume=(1/4)PI(.25)^2*15=.736... Mass= V*7800= 5743.2... I=(1/3)M*15^2=430741.8... 10^6=(1/2)Iw^2 w=sqrt(4.64...) w=2.15... w*2[for the 2 blades]=4.309... I tried the above value and was incorrect.
November 3, 2007

Physics
I can't seem to find where I've gone wrong... Volume=(1/4)PI(.25)^2*15=.736... Mass= V*7800= 5743.2... I=(1/3)M*15^2=430741.8... 10^6=(1/2)Iw^2 w=sqrt(4.64...) w=2.15... w*2[for the 2 blades]=4.309... I tried the above value and was incorrect.
November 3, 2007

Physics
M=7800*[(1/4)*PI*(.25)^2*15] KE=(1/2[(1/3)M(15)2]w^2=10^6 KE=2.15... x2 (for the two blades) KE=4.31 would that be in radians or revolutions?
November 3, 2007

Physics
How do I determine the volume of the blade so I can find the mass? I'm not quite sure what shape the figure actually is...
November 3, 2007

Physics
Tidal Energy. If we model 2 blades as thin uniform steel bars 15.0m long and .25m in diameter, at what rate (radians/second and revolutions per minute) must they spin for a turbine to store 10^6 J of energy? Keep in mind that the density of steel is 7800kg/m^3 and density is ...
November 3, 2007

Physics
A CD rotates at 500 (revolutions per minute) while the last song is playing, and then spins down to zero angular speed in 2.60 seconds with constant angular acceleration. The magnitude of the angular acceleration of the CD, as it spins to a stop is 20.1 radians per second ...
November 3, 2007

chemistry
what is the name of the polyatomic ion (C2O4)-1?
November 1, 2007

grammar
books, magazines, newspapers, and movies are either underlined or italicized, while other titles (such as that of a tv show) are put in quotes. the former (books, magazines, newspapers, and movies) is generally italicized when written on the computer, but underlined when ...
November 1, 2007

math
how do you find a percent like 19 out of 50 people like dogs
October 20, 2007

vocab
what is a sentence using it???
October 17, 2007

vocab
I have to do a presentation on the word contempt. I need to think of a fun way to review it and all the other words people presented. Please give me ideas! thank you!
October 17, 2007

science
how does the intertidal zone influence humans?
October 9, 2007

Spanish
i am not exactly sure what you are asking, but if you are looking for the meaning of de Sra, i can tell you that Sra stands for senora, which means de Sra means from the woman OR of the woman.
September 30, 2007

history
thanks. i tried the first site already, but could not find the information i needed. hopefully the third site will help. :)
September 30, 2007

history
what are some of the natural resources found in maryland?
September 30, 2007

science
how old is the sun and the planets? how did the solar system form? what is a good website i can get this information from?
September 13, 2007

math
how do u factor these polynomials~ 5x^2 - 5x-60 81-x^4 18a^2b-50b
September 4, 2007

Algebra 2
3x+2y=6 -6x-3y=-6
September 4, 2007

3(square root of -1)(2+5(square root of -1) -3(2+-5) -9=x+6(square root of -1) -9=x+-6 -9+-6=x -15=x
August 18, 2007

History
This is so dumb, but what year did the Spanish America war begin? http://en.wikipedia.org/wiki/Spanish-American_War
August 10, 2007

Science.
Whats the difference between a scientific theory and a regular theory? A theory may be about anything but a scientific theory is designed to explain some scientific principle. Why people shop at a certain store might be an ordinary theory but why AgCl is more soluble than AgBr...
August 9, 2007

Managerial Economics
The MorTex Company assembles garments entirely by hand even though a textile machine exists which can assemble garments faster than a human can. Workers cost \$50 per day, and each additional laborer can produce 200 more units per day (the same for each additional worker). ...
August 8, 2007

english
If a person's name ends with "the third," do you capitalize "third?" Yes, but it would be preferable to use the Roman numerals (III in this case) after the name. DrWLS is right. Here's an example: Richard III John Edward Jones III See?
July 28, 2007

english
what are the differences between... to wake and to awaken? AND to rouse and to arouse? Here are two discussions of the usage of these words. awake, awaken, wake (up): awake is usually an adjective: "I am awake." Awaken is always a verb, either transitive ("A ...
July 28, 2007

english
which is right...? Pollution, costs of living, and the threat of global warming IS rising. OR Pollution, costs of living, and the threat of global warming ARE rising. The subject is plural (pollution, costs of living, and the threat...), so the verb needs to be plural, too. ...
July 28, 2007

essay topic
I cannot think of a creative essay topic related to the subject of "energy efficiency in my home." Please help! You could write from the point of view of someone who is buying a brand new house and can select all the appliances -- and then do so with energy ...
July 27, 2007

arithmetic
you can email me if you want i have more. A man owned 75 shares of stock worth \$50 each. The corporation declared a dividend of 8 percent payable in stock. How many shares did he then own? 81 shares but how? If a scow is towed at the rate of 3 miles an hour, how many hours ...
July 25, 2007

science(chem) Dr.Bob (activity coeficent)
When a 0.1M solution of weak acid HA was titrated with a 0.1M NaOH. The pH measured when Volbase=1/2Voleq point was 4.62. Using the activity coeficents, calculate pKa. fA-=0.854 and fHA=1.00 For this I'm confused once again. I know that using the activity coeficents I can ...
July 24, 2007

math problems
thanks alot for giving me those sites but i already know this stuff. They dont teach how to read an aritmetic problem so its confusing to me what to do with them, when sometimes its so obvious i just need someone to actually explain it to me in a diffent ways, that i might be ...
July 24, 2007

arithmetics
ok i have a few more questions. this question. If a barrel has a capacity of 100 gallons, how many gallons will it contain when it is two-fifths full? I know its 40 gallons but how and why? this one also. the number of half-pound packages of tea that can be made up from a box ...
July 24, 2007

arithmetics
ok i understand now what 3/4 means and i know what 1/2 of a cup is but what does 3/4 of a cup mean. You can do it with blocks but not with how much is in the cup. I dont understand. will someone help me? You can do it with blocks. Let four blocks equal a cup, then three of ...
July 24, 2007

How many ml of 0.8M KOH should be added to 5.02g of 1,5 pentatonic acid (H2A) Mwt= 132.11 to give a pH of 4.4 when diluted to 250ml before the first eq point pKa1= 4.345 Is the answer 25.2ml? If that IS correct then I need help b/c I can't get that answer... I've got ...
July 23, 2007

I REALLY REALLY NEED this to be checked by the END OF THE Day since my finals are tomorrow and I need to know if this is the correct way to do this type of question PLEASE TELL ME IF IT IS CORRECT. I AM posting this again since nobody replied to the other one The total Carbon ...
July 23, 2007

science( chem)
The total Carbon dioxide content (HCO3- + CO2) in a blood sample is determined by acidifiying the sample and measuring the volume of CO2 evolved with a van slyke manometric apparatuses. The total concent was determined to be 28.5 mmol/L. The blood pH at 37o was determined to ...
July 22, 2007

science( chem)
When a 0.1M solution of weak acid HA was titrated with a 0.1M NaOH. The pH measured when Volbase=1/2Voleq point was 4.62. Using the activity coeficents, calculate pKa. fA-=0.854 and fHA=1.00 For this I'm confused once again. I know that using the activity coeficents I can ...
July 22, 2007

science( chem)
When 100.0ml of a weak acid was titrated with 0.09381M NaOH, 27.63ml were required to reach the equivalence point. The pH at the equivalence point was 10.99. What was the pH when only 19.47ml of NaOH had been added ? I'll just post my work and I need someone to check and ...
July 22, 2007

science( chem)
Find the pH of a solution prepared by disolving 1.00g of glycine amide hydrochloride (BH+) (mwt=110.54g/mol) plus 1.00g of glycine amide (B)(mwt=74.08) in 0.10L PKa=8.04 I got pH= 8.21 Is that correct? This question actually has 4 extra parts but I wanted to make sure I got ...
July 21, 2007

science(chem)
I posted this before but nobody replied so I'll post again... this is in reference to whether textbooks such as Fundamentals of analytical chem should be cited as a literature source in a lab report on the titration of wine with standardized NaOH IF I said that %tartaric ...
July 21, 2007

science( chem)
Calculate the molar solubility of Mg(OH)2 in water I know Mg(OH)2=> Mg2+ + 2OH- 2H2O=> H3O+ + OH- Ksp= [Mg2+][OH]2 Kw= [H30+][OH-] Mass balance [Mg2+]=2[OH] So.. [OH-]=2[Mg2+]+ [H3O+] Charge balance is where I get kind of confused I know that the positive charge is ...
July 20, 2007

science( chem)
For literature citation at the end of a lab report if only the text is used would that have to be cited as well? Or would it not be cited and on the page for literature citation I would type no sources cited? You have to cite anything and everything that is used along with the...
July 20, 2007

science( chem)
For the lab of Determining the % of iron in an iron ore sample The instructions were to: 1) Weigh out btw 0.3-0.4g of iron ore 2) disolve in concent HCl (10ml) and 3ml of 0.25M SnCl2 3) add enough tin so the yellow color disapeared 4) heat until sample decomposes and disolves ...
July 17, 2007

science(chem)
What is Zimmerman Reagent made of? (I know it is acidic b/c I was told after it burned a hole in my jeans) acid? You must mean Zimmermann-Reinhardt reagent (79 g MnSO4, 100 mL of concentrated H2SO4, and 200 mL of concentrated H3PO4, diluted to 1 L) Zimmerman reagent is equal ...
July 16, 2007

science(chem)
For an example of charge balance in my text it says Write a charge balance eqzn for an aqueous sol that contains NaCl, Ba(ClO4)2, & Al2(SO4)3 The answer given is: [Na+] + [H30+] + 2[Ba+] + 3[Al3+]= [ClO4-] + [NO3-] + 2[SO42-] + [HSO4-] + [OH-] I know that the rxns are: NaCl=&...
July 16, 2007

science(chem)
For Mass-Balance eqzns, in my text it is described as "relating the equillibrium concentrations of various species in a solution to one another and to the analytical concentrations of the various solutes. Is the analytical concentration described, the molar concentration...
July 15, 2007

science(chem)
Situation: KMnO4 solution left in buret for awhile...would it be okay to go and titrate with the same solution left in the buret later? And if solution is discarded and refilled later wouldn't the solution go and react with the light thus contaminating the new solution? ...
July 14, 2007

science(chem&statistics)
I have to write a abstract for my paper I was wondering if it was better to write it at the beginning or the end of the lab report. If I was to eliminate 1 value as an outlier would I go and include that in calculations of the RSD? I would assume not since It would affect the ...
July 12, 2007

science (chem& statistics)
For a wine titration my results obtained were... 0.6402%, 0.5814%,& 0.6006% the I calculated was 0.04936 according to my text sometimes the # is expressed in ppt or 100% first which would be correct if asked to submit a RSD for the results of a lab like this and 2nd what would...
July 10, 2007

science (chem)
Does EDTA react with light? I forgot to cover a dilute bottle of EDTA (about 0.01M) and was wondering if that would have any affect on the solution I don't think so. I have used EDTA many times and never covered it or used a tinted container. okay =) i posted an answer to ...
July 2, 2007

CULTURAL DIVERSITY
I need help with an assignment. I am asked to have someone fill out this worksheet. Can anyone Please help? Appendix D United States-Centric Views Comparison Consider this question: What are an average American’s perceptions about Muslim/Arab American and Christian ...
June 30, 2007

science (chem)
In general when instructions are to let a solution cool to room temp would it be incorrect to put the bottle containing the solution into a cold water bath so it could cool faster? Would it affect the solution in an adverse way? or does it depend on what you are cooling? ...
June 27, 2007

science (chem)
what is the chemical eqzn of Na2CO3 + HClO4? Na2CO3 + HClO4 ==> NaClO4 + H2O + CO2 I will leave it for you to balance. how did you get that DrBob The rule on carbonates is: An acid added to a carbonate yields carbon dioxide, water, and a salt. oooh so you had to know that ...
June 24, 2007

science (chem)
For the preparation and standardization of NaOH with KHP im supposed to boil water for 1hr and 30 min to remove CO2....the problem is that if I don't boil it for that long and (30 min) b/c of not enough time but I put the water I boiled for 1/2 hr aproximately into a NaOH ...
June 22, 2007

science (chemistry)
I have to do this lab where I titrate Na2CO3 with HCl dilute solution but i had to add Methyl orange indicator to the solution and im not sure what the endpoint is supposed to be colored, is it supposed to be orange or pink?? im confused and just how orange is it supposed to ...
June 21, 2007

CULTURAL DIVERSITY
Can anyone please read over my assignment and let me know if there are any grammar or spelling errors? CheckPoint: Modern Challenges in Immigration o Should United States government policy favor certain kinds of immigrants? o Should [citizenship] preference be given to the ...
June 15, 2007

Accounting
Hello, I need help with this case please: All Star Cards and Bubble Gum Cards recently formed a New Company “Baseball Trading Cards” in order to combine their respective wholly-owned baseball trading card business. In connection with the formation of Baseball Trading...
June 1, 2007

poetry
i need to write a question poem with 10 lines and that asks a lot of questions i have no ideas please help! Pick a theme, then the questions, then put them in verse. Example: Theme Love questions.. What is how it began where will it lead how will it end and so on... the verse...
May 14, 2007

math
the cost of 6oz. of chicken is \$2.00. how much would it cost for 1.5lbs. of chicken ? (16oz=1lb.) 2 simple ways: 1. if 6 oz cost 2.00 then 1 oz costs 2.00/6 = .3333. and then 16 oz cost 16(.3333..) =5.33 2. by ratios 2.00/6 = x/16 cross multiply and solve for x you will get ...
April 23, 2007

vocab
i need to know if you can change frothed into a verb, adjective, or adverb. and if it can have any prefixes or suffixes. Please help thanks! See my response below. Dictionary definitions will also include part(s) of speech. =) Frothed is a verb. Frothing can be an adjective (...
April 19, 2007

vocab
i need three more sentences using frothed please help!!! thanks so much it means to bubble or foam. i figured out some sentences but now i need to know if you can change it into a verb, adjective, or adverb. and if it can have any prefixes or suffixes. http://www.answers.com/...
April 19, 2007

Math URGENT!!
The speed of a runner increased steadily during the first three seconds of a race. Her speed at half-second intervals is given in the table. Find a lower estimate for the distance that she traveled during these three seconds. t(s) 0 0.5 1.0 1.5 2.0 2.5 3.0 v(ft/s) 0 3 6.6 9.9 ...
April 14, 2007

vocab
what does waylaid mean? http://dictionary.cambridge.org/define.asp?key=89472&dict=CALD
April 11, 2007

C++
Can anyone help me with my c++ program? Its a program I have to write using structs and arrays and i'm stuck. If anyone can help can you post back and I'll show you what i've got and maybe you can tell me why its not working correctly. Thanks I can try. I have not ...
April 4, 2007

english
i need help writing a "i am" metaphor poem. The format is 10 lines of I am metaphors and the 11th line is what you are like i am annoying or i am blonde or something. PLease help it is due tomorrow! Someone here will be happy to give you feedback on what you write. ...
April 2, 2007

Chemistry
A buffer is prepared by mixing 110. mL of 0.442 M HCl and 0.545 L of 0.400 M sodium acetate. How many grams of KOH must be added to 0.500 L of the buffer to change the pH by 0.10 units? The pH I have calculated to be 5.28. What do I to figure this out? I have a problem with ...
April 2, 2007

The Crucible (ACT TWO)
1.eight days
March 24, 2007

SOSE
Hey people! i really need some help here. im doing an assignment and i need info (sites) i need to no umm the average humidity, UV index, daylight, wind, storms, cyclones and any other things. please. oh, and i need it on townsville. so if anyone could find a site, and tell me...
March 13, 2007

history
Why was the u.s neutral at the beginning of world war I? http://en.wikipedia.org/wiki/World_War_I#Entry_of_the_United_States =)
March 12, 2007

Science..help plz...
Can you define speed, motion, constant speed and average speed? And can you get me there formulas? Example-Distance over speed THANKS MUCH! <333 constant speed is zero acceleration. speed is change of distance/change time Average speed= distance/time motion is the changing ...
March 4, 2007

science
when can the plant start to make its own food? A plant always makes its own food. Ever since it existed it made its own food through photosynthesis. The leaves take in the sunlight and form it into food. It also releases oxygen.
February 27, 2007

SCIENCE!!! help plz.... :-]
What is litum paper made of? If you cant find anything can you try to find some websites for me? THANKS A LOT!! 8-] litmus paper traditionally is a good grade (cotton) paper, with an extract of vegetable dye from the Litmus plant. http://www.botanical.com/botanical/mgmh/l/...
February 5, 2007

Chem
What is the formula for an oxide of fluorine? F2O2 also written as O2F2
December 7, 2006

physics
A 640 N student stands on a bathroom scale in an elebator. As the elevator starts moving, the scale reads 800 N. a) find the acceleration of the elevator (magnitude and direction) b) acceleration if the scale reads 450N? c) If the scale reads 0 should the student worry? ...
November 16, 2006

physics
A light rope is attached to a block with a mass of 6 kg that rests on a horizontal, frictionless surface. THe horizontal rope passes over a frictionless, massless pulley, and a block of mass m is suspended from the other end. When the blocks are released, the tension in the ...
November 16, 2006

Music
Do orchestral musician learn each work just before it is performed and have only a little amount of time to practice? I believe that this is not true. Is this right? Not true.
November 7, 2006

math
the 2-digit # that is divisible by both the sum and the product of its digits. i got 24 and 30, but would 30 count? in other words, is it ok that 30 is divisible by 0, the product of its digits? 30 isn't divisible by zero. Any number divided by zero is indeterminate so we ...
October 25, 2006

math
one of four #s where n! has n digits.
October 25, 2006

math
the largest integer that is not the sum of 2 or more different primes.
October 25, 2006

math
a # that is neither prime nor the sum of two distinct primes. are you doing that month of math thing?
October 25, 2006

math
one of two numbers that can be both the area and perimeter of a triangle whose side lengths are a Pythagorean triple.
October 25, 2006

math
the number of furlongs in a league. apparantly there are 8 furlongs in a mile, i learned this just today on my ride home form school. I hope this helps. go to www.google.com and type in 1 furlong to league and hit search. The answer will pop up at you. thanks again for your ...
October 25, 2006

math
the smallest non-palidronic number whose square is a palindrome.
October 25, 2006

math
the maximum number of pieces into which a pizza can be cut by making 6 cuts. Answer is from 1-31. The formula calculating the maximum pieces cut from a circle is: c*(c+1)/2 + 1, where c is the number of cuts. See math,hws,edu/~mitchell/Math135F05/Day18,pdf dots instead of ...
October 25, 2006

math
the smallest number of people in a room where the probability of two of them having the same birthday is at least 50 percent. Answer is between 1 and 31. This is a classic problem given in probability classes. There are plenty of sites which will give and explain the answer, ...
October 25, 2006

math
the radius of a circle when the numeric values of the circumference and area are equal. circumference = 2*pi*r area = pi*r^2 Set them equal and solve for r. thanks! i understand it now! 2*3.14*r=3.14*r^2 6.28*r=3.14*r^2 r=3.14 Is that right? It doesn't seem to be. 2*3.14*r...
October 25, 2006

Chemisrty
Yes. An elements number of neutrons and electrons can change, but its number of protons will not vary. Therefore, the atoms of the same element do have the same number of protons.
October 23, 2006

English
Which wife is more virtuous to her husband Desdemona or Emilia in the play Othello? Please use examples from the play to describe each womans interaction with her husband and each woman's reaction to her husband. I think you will be able to find the answer at either of ...
October 21, 2006

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