Popular questions and responses by Heather
  1. chemistry

    the reaction of 7.10g carbon with excess O2 yields 12.25g of CO2. what is the percent yield of this reaction? I have tried everything and looked through all of my notes and nothing is working for stiochiometry

    asked on October 6, 2014
  2. calculus 1

    A kite 100 ft above the ground moves horizontally at a speed of 10 ft/s. At what rate is the angle (in radians) between the string and the horizontal decreasing when 200 ft of string have been let out?

    asked on February 26, 2013
  3. Physics

    A sprinter explodes out of the starting block with an acceleration of +2.3 m/s^2, which she sustains for 1.2 s. Then, her acceleration drops to zero for the rest of the race. What is her velocity (a) at t=1.2 s ans (b) at the end of the race?

    asked on August 29, 2010
  4. Chemistry

    The amount of energy released by burning a fuel source, measured in energy per mass, is called the fuel value. If all the energy obtained from burning 1.28 pounds of methane (fuel value is 11.97 kcal/g) is used to heat 127.0 kg of water at an initial

    asked on February 11, 2012
  5. Physics

    Taking the age of Earth to be about 4 ✕ 109 years and assuming its orbital radius of 1.5 ✕ 1011 m has not changed and is circular, calculate the approximate total distance Earth has traveled since its birth (in a frame of reference stationary with

    asked on November 19, 2017
  6. chemistry

    A student placed 19.0g of glucose (c6h12o6) in a volumetric flask, added enough water to dissolve the glucose by swirling, then carefully added additional water until the 100ml.- mark on the neck of the flask was reached. The flask was then shaken until

    asked on February 28, 2010
  7. History

    If humanity has passed the point where the oil supply is declining, which suggests the most practical response? start hoarding oil in underground tanks as a hedge against a future without oil increase funding for government agencies like NASA to find other

    asked on August 5, 2018
  8. Physics

    At takeoff a commercial jet has a 45.0 m/s speed. Its tires have a diameter of 0.850 m. (a) At how many rpm are the tires rotating? Incorrect: Your answer is incorrect. rpm (b) What is the centripetal acceleration at the edge of the tire? 4764.70 Correct:

    asked on November 19, 2017
  9. History

    Which best suggests why Russia, China, and North Korea engage in malicious cyberattacks? The populations of these nations rank high in computer literacy. Their languages feature non-English fonts which aid encryption. They are renegade states beyond the

    asked on August 5, 2018
  10. math

    there are 4 blue tile,s 3 yellow tiles, 5 red tiles, and 2 green tiles. he draws a tile replaces it, and draws another tile. what is the probability he will draw a blue tile on both

    asked on May 19, 2014
  11. math

    The test scores for a math class are shown below 83,85,82,93,83,84,95,87,86,94 what is the standard deviation of the data set?

    asked on May 19, 2014
  12. Quantitative Reasoning (math)

    One out of every five people who buys ice cream buy vanilla ice cream. If a store sells 125 ice cream cones in one day, about how many will be vanilla? I know how to solve the proportion once I set it up, but I cant figure out how to set it up

    asked on September 10, 2014
  13. History

    What allowed for the shift of political and social ideas toward the heightening of anti-Semitism in Germany? Hermann Göering established the Gestapo to round up Jewish agitators and send them to labor camps. Josef Mengele reorganized the German film

    asked on August 11, 2018
  14. History

    Which identifies the relationship that Communist governments such as North Korea and China have with the media? News outlets are strictly prohibited by the government in Communist countries. The media has near-complete freedom in Communist countries as a

    asked on August 5, 2018
  15. History

    Which best describes the political relationship between oil-producing states and their consumers? Consumer states use their economic influence to persuade oil-producing states to set lower prices on oil. The government of an oil-producing state has a

    asked on August 5, 2018
  16. History

    Which identifies the Department of Homeland Security’s online operation that monitors the Internet to detect cyber threats? Comprehensive National Cybersecurity Initiative Cybersecurity Resource Center Cybersecurity National Action Plan National

    asked on August 5, 2018
  17. History

    Which factor most contributed to the economic growth of the Asian nations located on the western shores of the Pacific Ocean? Cooperative inter-Pacific trade partnerships gave smaller countries enhanced bargaining power in setting prices for goods. Reduced

    asked on August 5, 2018
  18. Physics

    In the figure, the two blocks are attached by a massless rope over a frictionless pulley, and block M1 slides on the table without friction. The masses of the blocks are: M1 = 8.10kg and M2 = 3.90kg. Calculate the tension in the rope. ( g = 9.80 m/s2)

    asked on February 14, 2016
  19. History

    How did the Chinese government react to the fall of Communist Russia? The Chinese government predicted that its own system could collapse, since it had been based on the Soviet Communist model. When Soviet states withdrew from the USSR, Chinese diplomats

    asked on August 5, 2018
  20. History

    How did Belgium rule in Rwanda contribute to genocide? Belgium rule led to the mass killing of Rwandans through ethnic cleansing. Belgium King Nicholas I ordered his army to execute Tutsis throughout Rwanda. Belgium favoritism toward Tutsis led to

    asked on August 5, 2018
  21. History

    Which most accurately describe the role colonies played within the global economy? (Select all that apply.) Many colonies were established as one-crop economies to provide cash crops to imperialist nations. Some colonies used laissez-faire economics to

    asked on August 10, 2018
  22. History

    Which cyberattack carries the most serious threat? A phishing attack on a chain store compromises customer data. A malware attack shuts down the power plants in a large city. Hackers launch a malicious code that shuts down Facebook. A Trojan horse virus

    asked on August 5, 2018
  23. English

    Can someone please confirm that my answers are correct? Choose the correct pronoun to fit the context of the sentence. 1. The dog chewed ________ leash apart. A. its B. his or her C. it’s D. their E. its’ I think it's C 2. Is technology with all

    asked on May 16, 2018
  24. History

    Which describes a cultural struggle faced in the Middle East? adopting Socialist views that emulate democratic Western policies replacing Islamic beliefs with Western cultural values lack of political support for religious beliefs at the regional level

    asked on August 5, 2018
  25. chemistry

    what is the density of an 84.7g sample of an unknown substance if the sample occupies 49.6cm3? what volume would be occupied by 7.75g of this same substance? PLEASE help need the answer tonight i have a test tomorrow i kind of not understand the second

    asked on September 22, 2010
  26. Social Studies

    The free-soil party was a persecutor to which political party? A. Know Nothing Party B. Whig Party C. Republican Party •• D. Copperhead Party

    asked on January 13, 2017
  27. History

    How did nations collectively intensify the conditions of the Great Depression? The breakdown in economic interdependence led to the inflation of multiple currencies worldwide and reduced international trade. The raising of tariffs in different countries

    asked on August 11, 2018
  28. music

    What is the main difference between Baroque and Classical music? I think barouge music is based on emotion but am not sure.

    asked on February 4, 2009
  29. History

    Which best defines electronic espionage? developing a pet restraint system that administers shocks through a collar teaching covert agents espionage skills through computer simulations spying on a government through the use of digital technology watching

    asked on August 5, 2018
  30. Chemistry

    What are the products of Ba(NO3)2(aq)+K2CO3(aq)?

    asked on September 22, 2012
  31. History

    Which most accurately traces the changing attitudes of the protesters during the year-long Arab Spring demonstrations? The protests began with Egyptian citizens calling for social reforms, but as protests spread, Tunisian fundamentalists urged the adoption

    asked on August 5, 2018
  32. History

    Which explains a consequence of the rise of global virtual markets? The growth of regional economies is limited to local resources. Virtual shopping limits the product selection from which consumers may choose. Regional economic growth often occurs as a

    asked on August 5, 2018
  33. pre-algebra

    Justin wants to use 376 ft of fencing to fence off the greatest possible rectangular area for a garden. What dimensions should he use? What will be the area of the garden? A. 89 x 99; 8811 ft B. 92 x 96; 8832 ft C. 94 x 94; 8836 ft D. 93 x 95; 8835 ft

    asked on July 26, 2017
  34. Chemistry

    Write the balanced chemical equation for the decomposition of sodium azide. If this is a redox reaction, show half reactions and determine if spontaneous. The chemical equation is 2NaN3(s) -> 2Na(s)+3N2(g) right? I am confused on the oxidation states for

    asked on October 8, 2012
  35. Chemistry Lab

    Hydrogen gas was collected over water in a eudiometer at 26 degrees celcius when the atmospheric pressure was 756 mm Hg. What was the pressure of the H2 gas?

    asked on October 15, 2012
  36. Algebra help please!

    Suppose you are researching the eating habits of people your age. What sampling method could you use to find the percent of students in your grade who eat five servings of fruit and vegetables each day? What is an example of a survey question that does not

    asked on April 14, 2014
  37. History

    How has the use of e-commerce impacted local markets? E-commerce has allowed for the rapid expansion of stock buying, which has increased the use of international manufacturing and reduced the need for local factories. Internet-based shopping has

    asked on August 11, 2018
  38. History

    Which best describes how the Korean War shaped the attitudes of the American public? American involvement in the Korean action created organized opposition that laid the foundations of the 1960s protest movements. Public outrage over the human cost of the

    asked on August 6, 2018
  39. trigonometry

    An airplane is flying at an elevation of 5150 ft, directly above a straight highway. Two motorists are driving cars on the highway on opposite sides of the plane, and the angle of depression to one car is 35° and to the other is 55°. How far apart are

    asked on December 2, 2012
  40. Physics

    A person pushes on a 56-kg refrigerator with a horizontal force of -251 N; the minus sign indicates that the force points in the −x direction. The coefficient of static friction is 0.7. (a) If the refrigerator does not move, what are the magnitude and

    asked on October 2, 2013
  41. History

    Which discuss the steps in the process that led to the social and political changes in South Africa? (Select all that apply.)

    asked on August 5, 2018
  42. physics

    A ball thrown horizontally at 13.0m/s from the roof of a building lands 21.4m from the base of the building. How tall is the building?

    asked on February 5, 2015
  43. physics

    A special electronic sensor is embedded in the seat of a car that takes riders around a circular loop-the-loop at an amusement park. The sensor measures the magnitude of the normal force that the seat exerts on a rider. The loop-the-loop ride is in the

    asked on February 23, 2011
  44. 4th grade math

    Write two 5-digit addends whose sum would give an estimate of 60,000

    asked on September 11, 2016
  45. Geometry

    #19. Given a regular octagon, find the measures of the angles formed by (a) two consecutive radii and (b) a radius and a side of the polygon.

    asked on April 8, 2014
  46. English

    Identify the subject and complete verb in each of the following sentences. 1. Please go to the store and buy some milk for the baby. A. you; go/store B. you; go/buy C. store; go/buy D. milk; go/buy I think that it's D (milk is the subject and go/buy is the

    asked on May 16, 2018
  47. History

    How did Japan attempt to solve its economic troubles during the Great Depression? The Japanese government began to invest in less capital-intensive industries to reduce overhead and promote international trade. The collapse of the US stock market caused

    asked on August 10, 2018
  48. Algebra

    Which of the following statements from Euclidean geometry is also true of spherical geometry? A) A line has infinite length. B) Two intersecting lines divide the plane into four regions. C) Two perpendicular lines create four right angles. D)The

    asked on October 17, 2011
  49. Quantitative Chemistry

    Ignoring activities, determine the molar solubility (S) of Zn(CN)2 in a solution with a pH = 2.92. Ksp (Zn(CN)2) = 3.0 × 10-16; Ka (HCN) = 6.2 × 10-10. Completely lost!

    asked on July 23, 2012
  50. Math

    Is the line through points P(3,-5) and Q(1,4) parallel to the line through points R(-1,1) and S(3-3)? Explain please.

    asked on March 9, 2014
  51. History

    Which describes the situation in Yugoslavia following the fall of the Soviet Union? Post-Communist Yugoslavia experienced an intellectual and cultural renaissance, but its stricken economy never recovered. Torn by conflicting nationalistic beliefs,

    asked on August 5, 2018
  52. Physics

    A soccer ball accelerates from rest and rolls 6.5 m down a hill in 3.1 s. It then bumps into a tree. What is the speed of the ball just before it hits the tree? A formula to answer this question would be fine; you don't have to solve the whole thing.

    asked on September 28, 2016
  53. physics

    The earth rotates once per day about an axis passing through the north and south poles, an axis that is perpendicular to the plane of the equator. Assuming the earth is a sphere with a radius of 6.38 x 106 m, determine the centripetal acceleration of a

    asked on February 23, 2011
  54. Algebra

    Michael's bank contains only nickels, dimes, and quarters. There are 63 coins in all, valued at $5.50. The number of nickels is 5 short of being three times the sum of the number of dimes and quarters together. How many dimes are in the bank?

    asked on July 30, 2018
  55. math

    What is the volume of a cone which has a base diameter of 14 units and a height of 12 units?

    asked on November 16, 2018
  56. pre algebra 1

    Sasha finished mowing lawns at 4:15 PM. It took 1^3/4 h to mow the first lawn. The second and third lawns she mowed each took 1^1/5 h. She took one 45-min break. When did Sasha begin mowing the first lawn? A. 10.05 A.M. B. 11:05 A.M. C. 11:21 A.M. D. 12:21

    asked on August 7, 2017
  57. Chemistry

    A 50/50 blend of engine coolant and water (by volume) is usually used in an automobile\'s engine cooling system. If your car\'s cooling system holds 4.90 gallons, what is the boiling point of the solution? Make the following assumptions in your

    asked on February 21, 2012
  58. science

    unit 4 lesson 13 the human body unit test review science 7a- unit 4

    asked on December 18, 2019
  59. Quantitative Reasoning (math)

    A round silo is 60 ft tall and has a 15 ft radius. About high would a load of 32,000 cubed feet fill the silo to? Do I start with pie*radius squared?

    asked on October 10, 2014
  60. Quantitative Reasoning (math)

    Your weight on the moon is relative to your weight on Earth. Neil Armstrong weighed 360 lbs. in his moon gear while on Earth, but on the moon he only weighed 60 lbs. What is the ratio of the Earth weight to the moon weight? How much would you weigh

    asked on September 11, 2014
  61. math

    In triangle PQR, m

    asked on May 19, 2014
  62. physics

    in 1993 bicyclist rebecca twigg of the united states traveled 3.00 km in 217.347 s suppose she travels the entire distance at her average speed and that she then accelerates at -1.72 m/s2 TO COME TO A COMPLETE STOP AFTER CROSSING THEfinish line hoew long

    asked on September 13, 2012
  63. College Business Statistic

    One operation of a mill is to cut pieces of steel into parts that will later be used as the frame for front seats in an automobile. The steel is cut with a diamond saw and requires the resulting parts to be within ±0.005 inch of the length specified by

    asked on July 7, 2012
  64. physics

    A satellite has a mass of 106 kg and is located at 1.96 106 m above the surface of Earth. (a) What is the potential energy associated with the satellite at this location? J (b) What is the magnitude of the gravitational force on the satellite? N

    asked on November 14, 2012
  65. Chem

    Sodium phosphate reacts with copper (II) chloride in a precipitation reaction. What mass (in grams) of the precipitate will form when 325 mL of 0.5000 molar sodium phosphate reacts with 41.5 cL of 0.6000 molar copper (II) chloride.

    asked on November 23, 2010
  66. English

    Can someone please confirm the following? 1. The yellow house down the street from me is for sale. (Down is underlined) a. preposition b. conjunction c. adjective d. adverb I think #1 is A, or C. 2. A pregnant person knows how difficult it is to get in and

    asked on May 18, 2018
  67. Confidentiality and Allied Health

    When should information be entered into a medical record? A at the time the event occurs b at the time set aside at the end of the shift c while the physician is making rounds d when the patient is discharged from the hospital I think its a

    asked on August 31, 2016
  68. health

    Americans spend almost _______ percent of their food budget on foods prepared away from home. A. 20 B. 30 C. 40 D. 50 Thinking it would be B.

    asked on July 26, 2017
  69. Spanish

    Could you please help proofread my paragraph for grammar and explain any issues thanks. An elementary bilingual teacher asks you to come to her class to talk to her students about how you used to celebrate the holidays with your family. First you want your

    asked on November 7, 2016
  70. Astronomy

    Where do you have to be on the Earth to see the Sun at your zenith? If you stay at one such location for a full year, on how many days will the Sun pass through the zenith?

    asked on February 2, 2011
  71. Algebra

    bicyclist rides 30 miles against a wind and returns 30 miles with the wind. his average speed for the return trip is 5mph faster. how fast did the cyclist ride against the wind if the total time of the trip was 5 hours

    asked on May 13, 2015
  72. Chemistry

    For a particular redox reaction NO is oxidized to NO3^- and Cu^2+ is reduced to Cu^+ . Complete and balance the equation for this reaction in basic solution. We are given this as a guide to start NO + Cu^2+ --> NO3^- + Cu^+ I started with: Cu^2+ + 2e- -->

    asked on April 9, 2014
  73. History

    How did the collapse of the Soviet Union impact Germany? Germany experienced violent protests that led to the execution of Ceausescu. Germany removed their capitalist leaders and adopted a new constitution. A German Socialist federation emerged, leading to

    asked on August 5, 2018
  74. Chemistry

    The reaction Co(H2O)6^+2 + 4Cl- CoCl^-2 + 6H2O is at equilibrium. The left side is pink and the right side is blue. 1. What would happen if you added AgNO3? Would nothing happen? Or would the Ag+ react with the Cl- and shift the reaction left? 2. What

    asked on March 18, 2010
  75. ratio

    given the proportion a/b=5/19, what ratio completes the equivalent proportion a/5= / ? a. a/19 b. b/19 c. 5/19 d. 19/b

    asked on March 19, 2014
  76. physics

    A neutron in a reactor makes an elastic head-on collision with a nitrogen atom that is initially at rest. (The mass of the nitrogen nucleus is about 14 times that of the neutron.) (a) What fraction of the neutron's kinetic energy is transferred to the

    asked on October 28, 2012
  77. ap history

    please help with this DBQ to what extent it is justified to characterize the industrial leaders of the 1865-1900 era as either robber barons or industrial states-man? ive looked at the internet but not much about industrial statesman. what do you think?

    asked on October 7, 2011
  78. Defense

    . Which of the following is not an example of an ethical dilemma a defense attorney may face? A) the prosecutor's winning record. B) client perjury. C) defense receipt of physical evidence. D) a confession in confidence. Would it be A?

    asked on March 22, 2015
  79. Chemistry

    The question says: A sample of helium is collected by displacing 182 mL of water. The pressures of the gas and the atmosphere are equalized, using the method described in this experiment. The atmospheric pressure is 738 mmHg. The temperature of the water

    asked on October 25, 2015
  80. chemistry

    The letters CHEMISTRY were spray painted in blue paint on the snow. After a while the sun comes out and the snow under the blue paint melts while the snow around the letters do not. Why did the snow under (rather than around) the blue paint melt?

    asked on November 19, 2013
  81. English

    Why does Jane Goodall describe the eyes of the chimpanzees using the words “dull and blank”? A) to show they have no feelings B) to show they are not smart creatures C) to contrast them with doctors D) to show how sad they are Is it A?

    asked on July 6, 2019
  82. Math Question

    Find an equation that models a hyperbolic lens with a=16 inches and foci that are 40 inches apart. Assume that the center of the hyperbola is the origin and the transverse axis is vertical

    asked on May 19, 2014
  83. chemistry

    If a tank contains 55.2 g of butane, what volume, in liters, of oxygen is needed to burn all the butane at 0.850 atm and 25 degrees Celsius? Need to show work too.

    asked on March 19, 2014
  84. Business Communications

    I wanted to welcome you ASAP to our little family here in the States. It's high time we shook hands in person and not just across the sea. I'm pleased as punch about getting to know you all, and I for one will do my level best to sell you on America. are

    asked on October 7, 2006
  85. English

    Identify each as fragment, run-on, comma splice, or sentence. 1. One legend has it that an old lady tried to dry off her sopping wet dog by putting it in the microwave this legend also predates the microwave oven. A. fragment B. run-on C. comma splice D.

    asked on April 18, 2018
  86. chem 130

    what mass of sodium hydroxide will be required to neutralize completely 1.60x10^23 molecules of HCl?

    asked on November 17, 2015
  87. math

    in the rhombus angle 1=140. what are angle 2 and angle 3? a. angle 2=140, angle 3=20 b. angle 2=40, angle 3=70 c. angle 2=40, angle 3=20 d. angle 2=140, angle 3=70

    asked on March 10, 2014
  88. trigonometry

    A 100-foot vertical antenna is on the roof of a building. From a point on the ground, the angle of elevation to the top and the bottom of the antenna are 51 degrees and 37 degrees, respectively. Find the height of the building to the nearest foot. How

    asked on December 9, 2012
  89. physics

    Robin is standing terrified at the end of a diving board, which is high above the water. If Robin has a mass of 56 kg and is standing 1.5 m from the board's pivot point, what torque is Robin exerting on the board?

    asked on October 27, 2016
  90. Physics

    A car is stopped at a traffic light. When the light turns green, the driver accelerates so that the car is going 10 m/s after 5s. What is the car’s average acceleration?

    asked on June 3, 2013
  91. English

    I looked at the website that was given to me last night. Can someone please tell me if my answers are right or wrong. Thank You Is this an example of imagery: Mrs. Wyman is so sweet sometimes you swear you can smell muffins baking. Is this an example of

    asked on October 1, 2010
  92. English

    Identify the part of speech or the form of a part of speech in the underlined portion of each sentence. 1. The yellow house down the street from me is for sale. (Down is underlined) a. preposition b. conjunction c. adjective d. adverb I think #1 is A, or

    asked on April 18, 2018
  93. physics

    A railroad car of mass 2.7 104 kg moving at 3.50 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s. (a) What is the speed of the three coupled cars after the

    asked on October 27, 2012
  94. English

    Choose the progressive or emphatic verb tense that is used in each sentence. 18.Ms. Palmer has been organizing the class schedules for us. present perfect progressive past progressive present progressive 19.We had been listening to the radio when the

    asked on April 24, 2012
  95. Math

    Suppose the price of an item increased by 8% a total of 13 times. By what percent did the price increase in total?

    asked on September 7, 2019
  96. Calculus

    Consider the illustration, which shows a rotating beam of light located 0.5 mile from a shoreline. The beam rotates at a rate of 4 revolutions per minute. How fast (in miles per minute) is the distance between the beam and the point where it strikes the

    asked on November 25, 2011
  97. College Math

    A card is selected from a standard deck of 52 playing cards. A standard deck of cards has 12 face cards and four Aces (Aces are not face cards). Find the probability of selecting · an even number ten or less given the card is a not a heart. · a five

    asked on September 9, 2011
  98. Physics: Newton's third law

    A passenger in a boat approaching a dock attempts to step onto the dock before the boat has been tied up. The passenger, whose mass is 57 kg, accelerated at a rate of 3.2 m/s^2 [forward]. If the mass of the boat is 97 kg, what is the boat's acceleration

    asked on March 22, 2019
  99. Physics

    A 555-g squirrel with a surface area of 945 cm2 falls from a 6.0-m tree to the ground. Estimate its terminal velocity. (Use the drag coefficient for a horizontal skydiver. Assume that the cross-sectional area of the squirrel can be approximated as a

    asked on November 19, 2017
  100. Inverse Functions

    A surveyor is standing 550 feet from the base of a redwood tree in the California Redwood Forest. The tree is 362 feet tall. Sketch a drawing that models the situation and then find the angle of elevation of the top of the tree from the spot where the

    asked on June 22, 2017


  1. 1
  2. 2
  3. 3
  4. 4
  5. 5
  6. 6
  7. 7
  8. 8
  9. 9