1. Chemistry

    Are these correct also? Ammonium Chloride : NH4Cl Nitrogen Dioxide : NO2 Hydroiodice Acid : HI Stannous Iodide : SnI2 Perchloric Acid : HClO4 Sulfur Trioxide : SO3 Chromium (III) Oxide : Cr2O3 Nitric Acid : HNO3 Diphosphorous Pentoxide: P205 Mercurous
  2. Chemistry

    Magnesium sulfate is often used it first aid hot-packs giving off heat when dissolved in water. When 2.00 g of MgSO4 dissolves in 15.0 mL of water (d= 1.00g/mL) at 25.0ºC, 1.51 kJ of heat is evolved. A) Write the balanced equation for this reaction. I
  3. college statistics

    the average length of time required for students to complete a test in a an introductory statistics course is found to be 50 minutes with a standard deviation of 12 minutes. if students are allowed 80 minutes to complete the test , approximately what
  4. Stat

    1. For the following scores, X Y 1 6 4 1 1 4 1 3 3 1 Sketch a scatter plot and estimate the value of the Pearson correlation. b. Compute the Pearson correlation 2. For the following set of scores, X Y 6 4 3 1 5 0 6 7 4 2 6 4 a. Compute the Pearson
  5. Physics

    On a string instrument of the violin family, the effective length of a string is the distance between the bridge and the nut. For a violin, this distance is 29.3 cm, while for a cello it is 37.8 cm. The string of a violin is placed in a cello with the
  6. physics

    On a string instrument of the violin family, the effective length of a string is the distance between the bridge and the nut. For a violin, this distance is 31.1 cm, while for a cello it is 38.8 cm. The string of a violin is placed in a cello with the
  7. Statistics

    1. The mean monthly mortgage paid by all home owners in a town is $2365 with a standard deviation of $340. a) Using Chebyshev’s theorem, find at least what percentage of all home owners in this town pay a monthly mortgage of (i) $1685 to $3045 & (ii)
  8. math

    1.The land on Earth’s surface is represented by the seven continents. Europe has 77% of the dry land while Africa has 20%. North America has 4/25 and Antarctica has 1/10 of the dry land. What fractional amount of the dry land is contained within the
  9. Math

    The percentage of people not covered by health care insurance in 2003 was 15.6% (Statistical Abstract of the United States, 2006). A congressional committee has been charged with conducting a sample survey to obtain more current information. a. What sample
  10. math help

    A salesman has to choose between two schemes of remuneration.The first scheme has a fixed salary of rs 3700 and a commission of 2% on sales above rs 50000. The second scheme has no salary but offer commission only. The commission starting from 3% of sales
  11. MATH

    A mean score on a standardized test is 50 with a standard deviation of 10. Answer the following a. What scores fall between –1 and +1 standard deviation? b. What percent of all scores fall between –1 and +1 standard deviation? c. What score falls at +2
  12. Statistics

    Age at onset of dementia was determined for a sample of adults between the ages of 60 and 75. For 15 subjects, the results were SumX=1008, and Sum(X-M)^2=140.4. Use this information to answer the following: a. What is the mean and SD for this data? b.
  13. Statistics

    Age at onset of dementia was determined for a sample pf adults between the ages of 60 and 75. For 15 subjects, the results were SumX=1008, and Sum(X-M)^2=140.4. Use this information to answer the following: a. What is the mean and SD for this data? b.
  14. Physics

    The intensity of sunlight reaching the earth is 1360 W/m^2 Part A: Assuming all the sunlight is absorbed, what is the radiation-pressure force on the earth? Give your answer in newtons. Part B: Give your answer as a percentage of the sun's gravitational
  15. history

    By how much is the hispanic population in Texas' public schools expected to increase by 2040? A 24% B 93% C 104% D 213% About what percentage of the population increase in Texas is due to people moving in from other states? A 12% B 22% C 32% D 42% Why have
  16. Chemistry

    Write a balanced equation using the correct formulas and include conditions (s,l,g or aq) for each of the following reactions. 1)Carbon monoxide gas reacts oxygen gas to produce carbon dioxide gas. Express your answer as a chemical equation. Identify all
  17. physics

    On a string instrument of the violin family, the effective length of a string is the distance between the bridge and the nut. For a violin, this distance is 30 cm, while for a cello it is 36.6 cm. The string of a violin is placed in a cello with the
  18. statistik

    the average starting salary of this yaer's graduates of a large university (LU)is $25000 with a standard deviation of $5000.futhermore,it is known that the starting salaries are normally distributed. a)what is the probability that a randomly selected LU
  19. University of Belize

    5. A 0.500 g sample of a BaCl2•2H2O/Na2SO4 salt mixture, when mixed with water, filtered, and dried, produced 0.225 g of BaSO4. The Na2SO4 was determined to be the limiting reactant. a. Calculate the mass, in grams, of Na2SO4 in the mixture. b. Calculate
  20. Please help (Bio)

    Measurements of oxygen binding by whole human blood, at 37oC, at pH 7.4, and in the presence of 40mm of CO2 and normal physiological levels of BPG (5 mmol/L of cells), give the following: PO2 (mm Hg) = 10.6, 19.5, 27.4, 37.5, 50.4, 77.3, 92.3 % saturation
  21. math

    DeWitt Company sells a kitchen set for $320. To promote July 4, DeWitt ran the following advertisement: Beginning each hour up to 4 hours we will mark down the kitchen set 8%. At the end of each hour, we will mark up the set 3%. Assume Ingrid Swenson buys
  22. prealgebra/ check answer please

    If 1,790 Mega Watts of power, out of the 3,000 Mega Watts generated by a power utility, reach the destination, what percentage of the generated power reaches its destination? 1,790 - 3,000 = 1,210 1,790 divided by 1,210 = 1.4 Answer 1.4% Unsure
  23. Chemistry

    In a reaction between methane, CH4 and chlorine, Cl2 four products can form: CH3Cl, CH2Cl2 + CHCl3 and CCl4. In a particular instance, 20.8 g of CH4 were allowed to react with excess Cl2 and gave 5.0 g CH3Cl, 25.5 g CH2Cl2+ and 59.0 g CHCl3+ all the CH4
  24. chemistry

    In a reaction between methane, CH4+ and chlorine, Cl2+ four products can form: CH3Cl, CH2Cl2 + CHCl3+ and CCl4. In a particular instance, 20.8 g of CH4 were allowed to react with excess Cl2 and gave 5.0 g CH3Cl, 25.5 g CH2Cl2+ and 59.0 g CHCl3+ all the CH4
  25. chem

    i have several problems i am caught on for my homework. I appreciate any help 1. As milk spoils, rancid components begin to coagulate. This could be interpreted as a: a.a colloid forming a suspension. b.solution forming a colloid. c.solution forming a
  26. calculus

    (1 pt) The acceleration due to gravity, g, is given by g = (G*M)/(r^2) where M is the mass of the Earth, r is the distance from the center of the Earth, and G is the uniform gravitational constant. (a) Suppose that we change from our distance from the
  27. immigrants U.S.A

    Immigrants U.S.A What do you want to know about immigrants to the U.S.A.? Since most of us are descended from immigrants -- who began arriving about four hundred years ago -- that's a lot of time and people. Please clarify your question and we'll try to
  28. science

    How many times did Earth orbit the sun between 140 CE and 1543 , how do you figure this up???? If you know how many years that is, the earth orbits the sun once a year. I hope this helps. Thanks for asking. How many years is 140 Ce to 1543 ?? We need to
  29. math

    can someone hep me please Population of Europe by Age Groups Population (in thousands) 1----------1950 --1970 --1995 Age 0-14--------143,175 166,367 139,464 Age15-64------- 359,162 421,432 487,110 Age 65+ 44,981- 68,642- 101,338 Age 75+ 14,553- 22,762-
  30. Chemistry

    Aspirin is prepared by heating salicylic acid, C7H6O3, with acetic anhydride, C4H603. The other product produced is acetic acid, C2H402. C7H6O3+C4H6)3->C9H8O4+C2H4O2 What is the theoretical yield in grams of aspirin, C9H8O4, when 2.00 grams of salicylic
  31. math

    The oil burner in a certain house is used to heat the house and to heat the hot water.During the seven cold months when the house is heated, an average of 200 gallons of oil a month is used.In the remaining five months, when the house is not heated, a
  32. Statistics

    Accrotime is a manufacturer of quartz crystal watches. Accrotime researchers have shown that the watches have an average life of 32 months before certain electronic components deteriorate, causing the watch to become unreliable. The standard deviation of
  33. chemistry

    Calculation of )Hf0 for Mg2+(aq.) 1. Assume the heat capacity of the final solution is 3.92 J K-1 g-1. Using the mass of the HCl solution, calculate qcontents from equation (4.6). Calculate qsystem from equation (4.5). 2. Calculate the moles of Mg2+
  34. Probability

    Serena Williams won the 2010 Wimbledon Ladies Singles Championship. For the seven matches she played in the tournament, her total number of first serves was 379, total number of good first serves was 256, and total number of double faults was 15. a. Find
  35. statistics

    A polling company reported that 53% of 2302 surveyed adults said that they play basketball.a. what is the exact value that is 53% of 2302? b. could the result from part (a) be the actual number of adults who said that they play basketball? why or why not?
  36. algebra

    Scientists can determine the age of ancient objects by a method called radio carbon dating. The bombardment of the upper atmosphere by cosmic rays converts nitrogen to a radioactive isotope 14C of carbon with a half-life of about 5710 years. Vegetation
  37. Business

    Envision that you run a highly successful tattoo and piercing parlor in a small West Coast city. You are fairly certain that between you and your key competitor, you have saturated your target audience of people in their teens and 20s. To grow your
  38. Chemistry

    Hi I just wanted to verify a few answers to chem questions I'm working on. Was wondering if anyone could help? 1. Calculate the molar concentration of 2.34g of lithium hydroxide, LiOH disolved in water to make 750ml of solution. My answer was CLiOH = 0.133
  39. Managerial Economics

    Textbook authors typically receive a simple percentage of total revenue generated from book sales. The publisher bears all the production costs and chooses the output level. Suppose the retail price of a book is fixed at $50. The author receives $10 per
  40. Statistics

    8. It is thought that prehistoric Indians did not take their best tools, pottery, and household items when they visited higher elevations for their summer camps. It is hypothesized that archaeological sites tend to lose their cultural identity and specific
  41. Statistics

    10. It is thought that prehistoric Indians did not take their best tools, pottery, and household items when they visited higher elevations for their summer camps. It is hypothesized that archaeological sites tend to lose their cultural identity and
  42. STATISTICS PLEASE HELP!!!!!

    are you a chocolate "purist", or do you like other ingredients in your chocolate? american demographics reports that almost 75% of consumers like traditional ingredients such as nuts or caramel in their chocolate. they are less enthusiastic about the taste
  43. Can comeone check my answer for me. Many Thanks!

    A set of data is normally distributed with a mean of 1000 and standard deviation of 100. · What would be the standard score for a score of 1100? · What percentage of scores is between 1000 and 1100? · What would be the percentile rank for a score of
  44. Health Help?

    1. A percentile rank represents the percentage of people who scored at or below the test score. True False 2. People who have high resting heart rates usually have high levels of cardiovascular fitness. True False 3. Resting heart rate is usually measured
  45. Math

    A. A survey of 110 teachers showed that 28 of them have a second job. B. A survey of 90 teachers showed that 27 of them have a second job. C. A survey of 70 teachers showed that 21 of them have a second job. D. A survey of 80 teachers showed that 32 of
  46. Chemistry

    1. Imagine that you work at a company that prepares chemical solutions. You are asked to label a solution to sell to different customers. One customer is a hospital, another is a chemistry lab at a university, and a third is a physics lab at a university.
  47. Stats

    G. Johnson recently inherited a large sum o money; he wants to use a portion of this money to set up a trust fund for his two children. The trust fund has two investment options: 1) a bond fund and 2) a stock fund. The projected returns over the life of
  48. Math Help

    Data released by the Department of Education regarding the rate (percentage) of ninth-grade students that don't graduate showed that out of 50 states, ​ 16 states had an increase in the dropout rate during the past 2 years. ​18 states had a dropout
  49. Bio (why no one is helpting?)

    Measurements of oxygen binding by whole human blood, at 37oC, at pH 7.4, and in the presence of 40mm of CO2 and normal physiological levels of BPG (5 mmol/L of cells), give the following: PO2 (mm Hg) = 10.6, 19.5, 27.4, 37.5, 50.4, 77.3, 92.3 % saturation
  50. Math

    The table shows the number of students in a middle school at the beginning of the year and the percentage that can be expected to move out of the area by the end of the year. 8. How many 7th grade students are expected to move by the end of the year? If 12
  51. phi 103

    mrs orlof teaches 2 history classes one in the afternoon and one in the morining yesturday she gave the same test to both classses anyone who failed the test must retake since a greater percentage of students who took the morining test failed the test than
  52. Chem-Stoich

    A 1.605g sample of dry calcium carbonate and calcium chloride mixture was dissolved in 35.00mL of 1.000mol-dm-3 hydrochloric acid solution. The only portion of the mixture that reacts with the hydrochloric acid solution is the calcium carbonate. What was
  53. Statistics

    A company that produces rivets used by commercial aircraft manufactures knows that the shearing strength (force required to breaking) of its rivets is a major concern. The company believes the shearing strength of its rivets is normally distributed with a
  54. CHEMISTRY! HELP

    I'm not sure how to do or show the work for these two questions. A) & B.)!! please anyone help: A.) Suppose a chemical reaction starts with 5.00 g of copper (i) nitrate and 2.00 g of magnesium chloride. Balanced Equation: 2 CuNo3 + MgCl2 ---> 2 CuCl +
  55. English IV

    How does the Hitchhiker's Guide to the Galaxy link to the British literature? Is Douglas Adams a British author? What do you do when a teacher hates you enough to fail you in that class? http://en.wikipedia.org/wiki/Douglas_Adams and
  56. Can someone Help w/Math

    Data released by the Department of Education regarding the rate (percentage) of ninth-grade students that don't graduate showed that out of 50 states, 16 states had an increase in the dropout rate during the past 2 years. 18 states had a dropout rate of at
  57. chemistry

    Determine the number of bromide ions in solution when 4.23 g of magnesium bromide and 1.21 g of potassium bromide are dissolved in 120mL of water. Please explain not sure how to even start this problem, thanks! chemistry - DrBob222, Wednesday, December 8,
  58. BIOLOGY

    PLEASE HELP ME! THANK YOU! The table shows the percentage of the body composed of water for various vertebrates. ANIMAL % OF BODY COMPOSED OF WATER herring 67 Frog 78 Chicken 74 Kangaroo rat 65 A)Which animal would you expect to have the most concentrated
  59. Math-Needing Help Quick!

    When Beth finishes college, she has a balance or $2876.37 on a credit card with an annual percentage rate (APR) or 17.3%. She decides to not make any additional purchases with her card until she has paid off the balance. Assuming the minimum payment is 2%
  60. stats

    You are a share analyst for an investment firm and are investigating the return on shares in the Eastern Mining Corporation over the last four years. The return on Eastern Mining Corporation shares over the last four years is presented. Calculate the
  61. Math

    You are a share analyst for an investment firm and are investigating the return on shares in the Eastern Mining Corporation over the last four years. The return on Eastern Mining Corporation shares over the last four years is presented. Calculate the
  62. AP CHEMISTRY

    The molar mass of an unknown organic liquid (M~100) is determined by placing 5 mL of the liquid in a weighed 125-mL conical flask fitted with a piece of Al foil with a pin hole in it. The flask is heated in a boiling water bath until the liquid evaporates
  63. Economics (37)

    According to the Sleep Foundation, the average night's sleep is 6.8 hours (Fortune, March 20, 2006). Assume the standard deviation is .7 hours and that the probability distribution is normal. a. What is the probability that a randomly selected person
  64. Statistics (37)

    According to the Sleep Foundation, the average night's sleep is 6.8 hours (Fortune, March 20, 2006). Assume the standard deviation is .7 hours and that the probability distribution is normal. a. What is the probability that a randomly selected person
  65. Chemistry

    In an experiment a student allowed benzene C6H6, TO REACT WITH EXCESS BROMINE BR2, in an attempt to prepare bromobenzene C6H5Br. This reaction also produced as a by-product, dibromobenzene, C6H4Br2, On the basis of the equation. C6H6 + Br2 -> c6h5Br + H
  66. chemistry

    In an experiment a student allowed benzene C6H6+ TO REACT WITH EXCESS BROMINE BR2+ In an attempt to prepare bromobenzene C6H5Br. This reaction also produced as a by-product, dibromobenzene, C6H4Br2+ On the basis of the equation. C6H6 + Br2 -> c6h5Br + H
  67. Economics

    I am having problems answering the question below can you please help? With probability p, you will catch a disease that reduces your income from y, its level when you are healthy, to y-k, where k > 0. A vaccine is available, at cost c, that reduces the
  68. water treatment

    A wastewater treatment plant based on activated sludge with biological phosphate and nitrogen removal via pre-denitrification. The influent flow (dwf) is 30,000 m3/day and the influent BOD concentration is 300 mg BOD/l. The suspended solid concentration in
  69. Math

    A certain college had 5,000 applicants and 3/8 of thes applicants were female. The college admitted 40 percent of all applicants and an equal number of male and female applicants. What is the percentage of female applicants admitted to the college? What is
  70. English

    Write this in your own words. what is Pollution? Pollution is the introduction of contaminants into the natural environment that cause adverse change.[1] Pollution can take the form of chemical substances or energy, such as noise, heat or light.
  71. Mis sue please save me

    A large school in the UK offers its pupils the opportunity to learn several non-English languages. It turns out that: • 55% of pupils in this school choose to learn French; • of the pupils who learn French, 40% also learn German. (c) Additional
  72. stats

    In September, the hospital had three coders who coded 1,500 inpatient records, and 22 of the records failed the quality screens. a.   What is the average number of records coded by each coder? b.   What was the average number of records coded each
  73. Chemistry

    1.The pH of a 0.10 mol/L aqueous solution of Fe(NO3)3 is not 7.00. The equation that best accounts for this observation is: a. Fe3+(aq) + 3H2O(l)<-->Fe(OH)3(aq) + 3H+(aq) b. NO3-(aq) + H2O(l)<-----> HNO3(aq) + OH-(aq) c. Fe(H2O)63+(aq) +
  74. Chemistry

    I posted this before and I know now to use P1T2=P2T1 but I was wondering what I would plug in as pressure and temp? just an example of one would be so great. In each of the four problem in this section, all gases are measured at the same temperature and
  75. Biology

    I would like some help if that is OK, like soon!:) 1.) A group of scientists proposes an idea that a chemical compound will enable bean plants to grow faster. They grow one group of bean plants in the presence of the compound and another group in the
  76. AP CHEMISTRY

    The molar mass of an unknows organic liquid (M~100) is determined by placing 5 mL of the liquid in a weighed 125-mL conical flask fitted with a piece of Al foil with a pin hole in it. The flask is heated in a boiling water bath until the liquid evaporates
  77. statistics and probability

    A company has been studying the performance of their sales department. The measure of performance used is: average monthly sales amount in dollars. For the past 12 months, the average monthly sales amount has been $4,532 with a standard deviation of $386.
  78. Physics

    A 23-kg child is sliding on an icy surface toward her mother at 3.0 m/s. Her 70-kg mother starts toward her at 2.0 m/s, intending to catch her. What percentage of the original kinetic energy is convertible? I calculated the convertible kinetic energy as
  79. Chem (ques 2)

    The analysis of some household cloudy ammonia cleaner involved diluting a 50.0mL sample of the cleaner to a volume of 250.0mL then titrating this diluted solution. The diluted sample was found to have an NH3 (aq) concentration of 0.350 mole per L. What is
  80. Pre-Algebra

    P.S - I really need help please help me with this, please i try and still i can not do this please!!!!!! :( :( :( :( :( The table below shows the percentage of households that own a microwave in different countries. Construct a stem-and-leaf plot of the
  81. stats

    Suppose that the average amount paid by customers at a grocery store is $80. The standard deviation of the amounts paid is $24. The distribution of the amounts paid is skewed. (Notice that the individuals here are customers and the variable is the amount
  82. Heath help Plz--5 questions

    1. A percentile rank represents the percentage of people who scored at or below the test score. True** False 2. People who have high resting heart rates usually have high levels of cardiovascular fitness. True ** False 3. Resting heart rate is usually
  83. Health--check my answers

    1. A percentile rank represents the percentage of people who scored at or below the test score. True False 2. People who have high resting heart rates usually have high levels of cardiovascular fitness. True False 3. Resting heart rate is usually measured
  84. chemistry help!

    I have a chemistry test tomorrow and I'm trying to study but none of these questions in the book make sense to me:( Help! 1. Commericially available concentrated sulfuric acid is 95% H2SO4 by mass and has a density of 1.84g/mL. How many milliliters of this
  85. science

    Hi I have 2 questions I hope someone can help me :) 1)A pocket of gas is discovered in a deep drilling operation. The gas has a temperature of 480c and is at a pressure of 12.8 atm. What volume of gas is required to provide 18.0 L of gas at the surface
  86. astronomy

    Using the densities below, find what percentage of the Earth's mass is contained in its core. If Earth's core were adjusted in radius so that the core contained forty percent of the mass, by what factor would the radius of the Earth change compared with
  87. Chemistry pls clearly step step for me

    2gm of mixture hydrated sodium carbonate and sodium bicarbonate was dissolved in water and made up to 250cc. 25cc of this solution was titrated using methyl orange as indicator and 22.5cc of 0.087N hcl were required for naturalization. calculate the
  88. math

    can someone hep me please Use the following tabe to answer the question. Population of Europe by Age Groups Population (in thousands) 1----------1950 1970 1995 Age 0-14 143,175 166,367 139,464 Age15-64 359,162 421,432 487,110 Age 65+ 44,981 68,642 101,338
  89. math

    can someone hep me please Use the following tabe to answer the question. Population of Europe by Age Groups Population (in thousands) 1950 1970 1995 Age 0-14 143,175 166,367 139,464 Age15-64 359,162 421,432 487,110 Age 65+ 44,981 68,642 101,338 Age 75+
  90. Reading

    I have this really long passage about how organic farming started small, but it grew quickly. From 1990 to 2010, sales of organic food in the United States increased from $1 billion to $26.7 billion. Fruits and vegetables represent the biggest percentage
  91. finance

    A thirty-year U.S. Treasury bond has a 4.0 percent interest rate. In contrast, a ten-year treasury bond has an interest rate of 3.7 percent. If inflation is expected to average 1.5 percentage points over both the next ten years and thirty years, determine
  92. Maths

    A large school in the UK offers its pupils the opportunity to learn several non-English languages. It turns out that: • 55% of pupils in this school choose to learn French; • of the pupils who learn French, 40% also learn German. (c) Additional
  93. Statistics

    Assume that the points scored by the winning teams for all NCAA games follow a bell-shaped distribution. Using the mean of 76.5 and the standard deviation of 7, estimate the percentage of all NCAA games in which the winning team scores 84 or more points.
  94. Chemistry

    Ok so I realize this is a lot of questions, but if someone could at least just give me the general set up for each problem that would save my life! In each of the four problem in this section, all gases are measured at the same temperature and pressure. 1)
  95. Maths Percentage (6th Grade)

    David has $5 in his wallet. This was 10% of the amount that he received from his mother. Find the total amount of money that David received from his mother. 35% of the number of books Ibrahim owns are fiction boos, find: a.) the total number of books he
  96. Statistics

    The USDA size standards for eggs are based on weight and are as follows: SMALL: greater than 43 grams, less than 50 grams MEDIUM: greater than 50 grams, less than 57 grams LARGE: greater than 57 grams, less than 64 grams EXTRA LARGE: greater than 64 grams,
  97. chemistry

    Can someone please help me with these? How many electrons would Nitrogen, Aluminum, and Bromine gain or lose? Look at the periodic table and find N, Al, and Br. You should find N in group VA (or 15 depending on the system being used), Al in IIIA (or 13),
  98. waste water treatment

    Description A wastewater treatment plant based on activated sludge with biological phosphate and nitrogen removal via pre-denitrification. The influent flow (dwf) is 30,000 m3/day and the influent BOD concentration is 300 mg BOD/l. The suspended solid
  99. Calculus

    Suppose a cylindrical can is manufactured with radius r. The manufacturing process makes the length r imprecise; r can be off by ±0.03 cm. The manufacturing process makes the height of the can precisely equal to three times the radius r (including any
  100. statistics

    A manager for a firm that sells advertising space in magazines and periodicals is considering a number of new initiatives to recognize high-performing members of her sales force. Assume that the annual sales revenue for members of her sales force is