Most popular questions and responses by Gemma
  1. Algebra

    What is the length of the hypotenuse of a right triangle with legs of 5 and 12 units? What is the "hypotenuse" and "legs" of a triangle? Thanks!

    asked on May 30, 2009
  2. earth's systems

    What are the four earth systems? and how do they interact with eachother? Lithosphere, Biosphere, Atmosphere, and Hydrosphere. They operate in an integrated fashion. I recommend you cite some specific interactions. all of the systems work together by air

    asked on April 10, 2007
  3. Chemistry

    The mass of potassium iodate (KIO3) contained in an impure sample was determined by titration with sodium thiosulfate (0.1005 M). The impure KIO3 was dissolved in 50 cm 3 of water, an excess of potassium iodide (KI) and 5 cm^3 of dilute sulphuric acid was

    asked on October 2, 2016
  4. chemistry

    Is melting endothermic or exothermic? Things that are melting are taking on heat, endothermic Would freezing be the same? No, of course not. If melting is endothermic, then freezing must be exothermic. Believe it or not, and I know it sounds goofy,

    asked on November 5, 2006
  5. Chemistry

    A student completes a titration by adding 12.0 milliliters of NaOH(aq) of unknown concentration to 16.0 milliliters of 0.15 M HCl(aq). What is the molar concentration of the NaOH(aq)?

    asked on April 13, 2010
  6. Algebra

    A turbo-jet flies 50 mph faster than a super-prop plane. If a turbo-jet goes 2000 miles in 3 hours less time than it takes the super-prop to go 2800 miles, find the speed of each plane. I do not understand how to do this at all. Please explain as well as

    asked on May 24, 2009
  7. Math

    Jean has a total of 24 coins consisting of just quarters and nickels. The coins total $3.40. How many of them are quarters?

    asked on December 9, 2013
  8. Algebra

    Do you know a site with some practice problems for a quadratic formula (ax^2 + bx + c) for my test tomorrow? Thank you so much!

    asked on May 28, 2009
  9. chemistry

    standard enthalpies of formation H20(l) = -286 LiOH(s) = -487 standard enthalpies of solution for LiOH(s) to split into it's ions is 21 all values are in KJmol-1 Use the data given to calculate a value for the enthalpy change for the reaction of lithium

    asked on February 8, 2011
  10. Algebra

    A long-distance call using DEC costs 20 cents for the first minute and 16 cents for each additional minute. The same call, placed on LCS, costs 19 cents for the first minute and 18 cents for each additional minute. For what length of phone calls is DEC

    asked on January 24, 2009
  11. Biochemistry

    Preform dilution calculations for 10 ml of 2 M stock solution. Molecular weight for the component is 48.6 g / mol

    asked on March 3, 2013
  12. chemistry

    Calculate the concentration of nitrate ions, NO3- , in mol dm-3, of a solution made by dissolving 2.5000 g of ferric nitrate nonahydrate in water to give 2.000 L of solution.

    asked on January 30, 2012
  13. algebra

    Mandi can be paid in one of two ways: Plan A-- A salary of $400 per month, plus a commission of 8% gross sales; or Plan B-- A salary of $610 per month, plus a commission of 5% of gross sales. For what amount of gross sales should Mandi select Plan A? I

    asked on January 24, 2009
  14. math

    Given: f(closure(A)) subset of closure(f(A)) Prove: For any closed set A in Y, f^-1(A) is closed in X (AKA f is continuous) X and Y are metric spaces f: X -> Y f^-1 is f inverse. closure(A) = A U limit points of A The first line is Let C be a closed subset

    asked on April 14, 2013
  15. physics

    At what force would a 16k object travelling at 25mph hit a stationery object

    asked on March 6, 2015
  16. English

    Do you hyphenate 3D or leave it one word?

    asked on October 17, 2009
  17. Chemistry

    P4 (g) + 3O2 (g) P4O6(s) At a particular temperature, Keq = 4.6. If [P4O6] at this temperature is 1.2M, calculate the concentration of P4 and O2 I'd rather have someone tell me how to do it, so I can do it myself since it's in preparation for an exam.

    asked on November 19, 2015
  18. Math

    Whats my rule Input 140. Output. 22 Input 100. Output. 62 Input. 91. Output. 71 So if the input is 10 what is the output?

    asked on May 13, 2014
  19. maths

    prove by mathematical induction that 7n+4n+1 is divisible by 6

    asked on October 31, 2012
  20. Biology

    what differences would there be in the product cells at telephose II of meiosis if there had been one crossing over at a position halfway between the Huntington disease gene and the centromere.

    asked on April 10, 2007
  21. chemistry

    calculate the mass of iron in 2.5000g of feric nitrate nonahydrate Fe(NO3)3.9H2O

    asked on February 4, 2012
  22. music

    for my music homework i have to do a poster on mozarts minuets and i don't know anything about him .please help!!!!!!!!!!!!!

    asked on June 28, 2011
  23. Chemistry

    A biomass power station burns forestry residue which has 2000 ppm potassium in it and produces 2% ash by weight (think Ive worded that right). I need to find the fraction of K2O in the ash, but only the fraction of K in the fuel as a whole is given.

    asked on February 7, 2011
  24. Chemistry

    what is the pH of Sulphuric acid? It depends upon the molarity. pH = -log(H+) -log = ? pH = -log(H^+) find (H^+), punch that into your calculator, change the sign to minus, then find the "log" key and punch that. That will be the pH.

    asked on March 12, 2007
  25. Science

    which action would result in the more (financially) valuable product: taking one proton from each nucleus in a sample of gold or adding one proton to each gold nucleus? Taking a proton (p) away 79 AU - 1p = atomic number 78?? Adding a Proton Au79 + 1p =

    asked on March 12, 2007
  26. science

    A 0.21 g of Sulfuris acid is dissolved completely in sufficient water to make 0.25 litre of final solution. Calculate the hydrogen ion concentration (in mol 1 -1) in this solution. Give your answer in scientific notation to an appropriate number of

    asked on March 6, 2007
  27. History

    were there any similarities between the roman emperors nero and caligula, and the roman general mark antony?

    asked on November 18, 2015
  28. Geometry

    Given circle A with circumference 20 pi and the length of arc KD equal to 10/3 pi. Find the area of the shaded region. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Is there any way I can post a diagram?

    asked on March 6, 2011
  29. Art

    I need to know about the symbolism in Olympia, can you explain what this means please.

    asked on January 16, 2011
  30. science

    Gametes produced in the process of meiosis in humans (chromosome 4)has a long and short arm the short arm has the gene for Huntington's (H) attached and the long arm the gene for Red hair (R) state the differences in the product cells at telophase II if a

    asked on April 10, 2007
  31. Chemistry

    suppose that ununhexium undergoes a succession of a-decays reactions. What isotype would be the final product? how did you arrive at this answer? and is it a lanthanide, actinide, transition or typical element? See the post above as a response to bertie.

    asked on February 6, 2007

    GIVE THE EMPIRICAL FORMULAE OF THE HIGHEST HYDRIDE AND HIGHEST FLUORIDE OF UNUNHEXIUM, EXPLAINING HOW YOU ARRIVED AT YOUR CONCLUSIONS Here is the web site for a very good periodic table. Look for element #116, Uuh. Elements in the periodic table have

    asked on February 6, 2007
  33. ives

    what is the area of the largest square that can be cut from a circle of radius 1?

    asked on February 6, 2017
  34. Maths (Coordinate Geometry)

    A point P(x,y) moves so that the line joining P to A(9,-5) is perpendicular to B(4,5). Derive an equation specifying the locus of P.

    asked on May 8, 2016
  35. Medical billing

    2nd question, pt present for PO check of head wound Pariental area healed well. RTO prn ( pf hx/px/sf/mdm) what is the code...

    asked on December 4, 2011
  36. Medical billing

    Pt present for suture removal. sutures removed and slight oozing occurs in midsection of wound. wound dressed and pt advised to aply antibaterial cream daily. retn in 4 to 5 days for final check(PF HX/PX SF/MDM...WHAT IS THE OV

    asked on December 4, 2011
  37. MATH

    is there anyway that a diagram or something can be drawn or pasted into the question box for a math problem?

    asked on March 6, 2011
  38. hospitality

    give 2 legal obilgations of manufacurers and employers with regards to cleaning agents

    asked on February 17, 2010
  39. Algebra-- PLEASE help!

    (x+3/4)^2 = 17/16 My teacher taught us a square root method, but I am confused with it on this one! I would prefer if you show me using square roots, but if you have another way, please help too! Thank you!

    asked on May 12, 2009
  40. Biology, please help

    Gametes produced in the process of meiosis in humans (chromosome 4)has a long and short arm the short arm has the gene for Huntington's (H) attached and the long arm the gene for Red hair (R) state the differences in the product cells at telophase II if a

    asked on April 10, 2007
  41. science

    I am writing an essay on the subject of, 'The metabolism of green plant cells in relation to energy exchange process.' Can anyone advise of key ideas to include please? This is a very, very complicated subject. Look here:

    asked on April 9, 2007
  42. science

    When an acid and an alcohol react does it produce an ester? If so ehat type of reaction is this? I call it esterification. It is also an elimination reaction in that water is eliminated.

    asked on March 12, 2007
  43. maths

    3. Suppose that a particle moves in a plane with trajectory given by the polar equation r=2bsintheta for some constant b > 0.Show that this can be written in Cartesian coordinates as,x^2 + (y-b)^2 = b^2;This is the equation for a circle of centre (0; b)

    asked on February 20, 2013
  44. medical billing

    help ...Pt present for suture removal. sutures removed and slight oozing occurs in midsection of wound. wound dressed and pt advised to aply antibaterial cream daily. retn in 4 to 5 days for final check(PF HX/PX SF/MDM...what is the code

    asked on December 4, 2011
  45. earth

    sam weighs 720N on the earth and 120N on the moon.what does this tell you about the value of gravity on the moon?

    asked on November 6, 2011
  46. To Adam/Anthony/Hols

    Any help with s103 06 QUESTION 5?? You would do better, I think, to post your question and let everyone try to help rather than using only students taking the course.

    asked on March 12, 2007
  47. Chemistry

    I know that Ununhexium is in period 7, group 16. What evidence would be able to support this? Here is a web site for an on-line periodic table. Look for Uun, element #116. That will give you the info you need.

    asked on February 6, 2007
  48. art

    where does banksy come from

    asked on October 15, 2008
  49. re

    for my re homework i need to find 3 pieces of evidence of what jesus did and 3 pieces of evidence what jesus didn`t do . i only need a little bit of info not pages of it. thanks!

    asked on September 22, 2008
  50. science

    what is the meaning of a glycosidic C-1 to C-4 linkage? Since this is not my area of expertise, I searched Google under the key words "glycosidic C-1 to C-4 linkage" to get these possible sources:

    asked on March 18, 2007
  1. Chemistry

    Is that correry?

    posted on October 4, 2016
  2. Chemistry

    I got 0.1099g

    posted on October 3, 2016
  3. Chemistry

    How do I find mL?

    posted on October 3, 2016
  4. maths


    posted on October 31, 2012
  5. maths

    its 7^n+4^n+1

    posted on October 31, 2012
  6. medical billing

    I did using my materials but I get comfuse do I code twice.

    posted on December 5, 2011
  7. cook

    I beieve is Gumbo

    posted on December 4, 2011
  8. Medical Billing

    diagnose is 681.11 E/M 99202, I&D great toe 10060 modifier TA, Excision great toe 11750 modifier TA, and 99024 PO check..

    posted on December 4, 2011
  9. Geometry


    posted on March 6, 2011
  10. Geometry

    The shaded region is between IKD THere are to lnes opposite of each other. Then to parallel lines through those lines. Thers is a circle in the middle with a circumference of 20 pi. THen there is a triangle that connected to the outer lines to the right.

    posted on March 6, 2011
  11. chemistry

    Molarity = moles/volume (dm3) so you need to convert your volume into dm3. 1dm3 = 1000ml so your equation should be; molarity = 0.56/0.100 = 5.6moldm-3

    posted on February 9, 2011
  12. chem

    Not sure about the KBr and the sand but iron is magnetic so that can be removed with a magnet. Sorry I cannot answer fully.

    posted on February 8, 2011
  13. Chemistry

    The first step would be to calculate the MR's of each substance so you could get the reacting masses so: 3H2 = (3 x 2 x 1) = 6 N2 = 14 x 2 = 28 2NH3 = (2 x 14) + (2 x 3 x 1) = 34 so in theory you need 6litres of H2 and 28litres of N2 to produce 34litres of

    posted on February 8, 2011
  14. Chemistry

    Electrostatic bonding forces relates to covalent compounds and the shared pair of electrons, it is when the nucleus of one atom attracts the electron of another atom and the electrons become shared between the two atoms. All you need to do now is pick out

    posted on February 8, 2011
  15. chemistry

    Use the formula moles = mass/Mr Mr of sodium = 23 Rearrange the equation to make mass the subject. mass = moles x Mr and put in the numbers... mass = 2 x 23 = 46g Hope this helps

    posted on February 8, 2011
  16. chemistry

    You need to know the formula for silver nitrate which is AgNO3 Then you work out the MR of silver nitrate = 108+14+(16x3) = 170 Then you work out the MR of the nitrogen contained in silver nitrate. There is just one nitrogen atom so it would be 14. Then

    posted on February 8, 2011
  17. Chemistry

    first of all you would need to find out the number of moles in solution using moles = mass/Mr Mr of AgNO3 = 108+14+(16x3) = 170 moles = 1.70g/170 = 0.01 Then you can use the formula: concentration = moles/volume(dm3) = 0.01/0.250 = 0.04moldm-3 hope this

    posted on February 8, 2011
  18. algebra

    Thank you for your help!

    posted on January 24, 2009