# Heather

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

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?

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?

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

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

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

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

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:

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

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

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?

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

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

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

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

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

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

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)

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

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

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

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

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

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

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

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

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

28. ## music

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

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

30. ## Chemistry

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

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

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

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

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

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?

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

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

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

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

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

41. ## History

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

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?

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

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

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.

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

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

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

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!

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.

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,

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.

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

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?

55. ## math

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

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

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

58. ## science

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

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

61. ## math

In triangle PQR, m

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

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

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

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.

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

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

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.

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

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?

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

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- -->

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

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

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

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

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?

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?

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

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?

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?

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

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.

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

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.

86. ## chem 130

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

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

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

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?

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?

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

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

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

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

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?

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

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

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