Most popular questions and responses by joey
  1. Vince

    Please show work for Determine the final end (final) value of n in a hydrogen atom transition, if electron starts in n = 1 and the atom absorbs a photon of light with an energy of 2.044 X 10^-18J? thank you very much for your help

    asked on September 17, 2015
  2. physics

    A uniform solid sphere rolls down an incline. (a) What must be the incline angle if the linear acceleration of the center of the sphere is to have a magnitude of 0.20g? 1° (b) If a frictionless block were to slide down the incline at that angle, would its

    asked on January 5, 2011
  3. physics

    Extreme-sports enthusiasts have been known to jump off the top of El Capitan, a sheer granite cliff of height 910m in Yosemite National Park. Assume a jumper runs horizontally off the top of El Capitan with speed 5.0m/s and enjoys a freefall until she is

    asked on April 21, 2012
  4. American Government

    The question in every case is whether the words used are used in such circumstances and are of such a nature as to create a clear and present danger that they will bring about the substantive evils that Congress has a right to prevent. –Schenck v. United

    asked on December 12, 2016
  5. Precalculus

    The height (in centimeters) of a candle is a linear function of the amount of time (in hours) it has been burning. When graphed, the function gives a line with a slope of -0.4 . Suppose that the height of the candle after 13 hours is 24.8 centimeters. What

    asked on March 24, 2014
  6. math

    The area of the base of a rectangular juice box is 4 1/2 square inches. If the volume of the box is 18 cubic inches, how tall is the box?

    asked on April 27, 2015
  7. statistics

    Determine the sample size required to estimate a population proportion to within 0.032 with 95.7% confidence, assuming that you have no knowledge of the approximate value of the sample proportion. Sample Size = B. Repeat part the previous problem, but now

    asked on March 28, 2009
  8. Calculus

    A construction company wants to build a rectangular enclosure with an area of 1000 square feet by fencing in three sides and using its office building as the fourth side. Your objective as supervising engineer is to design the enclosure so that it uses the

    asked on August 9, 2011
  9. Biology-check my answer

    Hershey and Chase used the 35S isotope to label proteins. How does this isotope differ from the 32S isotope found in greatest natural abundance, and why did they choose 35S instead of 32S? A)35S has more protons than 32S; Hershey and Chase used it because

    asked on December 19, 2012
  10. Calculus (optimization problem)

    A cyclinderical tank with no top is to be built from stainless steel with a copper bottom. The tank is to have a volume of 5ð m^3. if the price of copper is five times the price of stainless steel, what should be the dimensions of the tank so that the

    asked on March 24, 2010
  11. Biology- check my answer (diff one)

    Which of the following are true concerning living things? Check all that apply. A)They contain a vital force absent in nonliving things. B)They are composed of molecules that contain carbon-carbon bonds. C)They undergo chemical reactions to use energy they

    asked on December 19, 2012
  12. Chemistry

    1- Determine the [OH-] and pH of a solution that is .250 M in HCO-3 2- Calculate the [H3O+] and pH of each polyprotic acid solution: a) .125 M H2CO3 b) .125 M H3C6H5O7

    asked on March 14, 2011
  13. Geometry

    the steps that you would follow to recreate a triangle using a protractor, a string, and the AAS Congruence Theorem, written out in words. I'm lost know that you need two angles and a side.No clue how to explain. Please help I've been sitting here all day

    asked on October 26, 2017
  14. 6th grade math

    A chocolate bar is separated into several equal pieces. If one person eats 1/4 of the pieces, and a second person eats 1/2 of the remaining pieces, there are six pieces left over. Into how many pieces was the original bar divided?

    asked on August 27, 2009
  15. physics

    A plum is located at coordinates (-4.0 m, 0.0 m, 6.0 m). In unit-vector notation, what is the torque about the origin on the plum due to force F whose only component is indicated by each of the following equations? (a) Fx = 8.0 N ô = N · m (b) Fx = -5.0

    asked on January 5, 2011
  16. Chemistry Dimensional analysis

    A cyclist rides at an average speed of 18 miles per hour. if she wants to bike 212km, how long in hours must she ride? What I have so far.. 212km(10^3 miles

    asked on February 7, 2016
  17. Algebra

    Find the sum of the following series. 14 n=1 (2n+1) A. 448 B. 256 C. 240 D. 224

    asked on May 22, 2019
  18. Pre-Algrebra

    Two cell phone companies have different rate plans. Runfast has monthly charges $10 plus $4 per gig of data. B A &D’s monthly charge is $6 plus $6 per gig of data. Your task, is to determine under what circumstances each company has the better pricing.

    asked on June 1, 2018
  19. science

    Suppose that the 1.3 km span of the golden gate bridge had no expansion joints. Calculate how much longer the bridge would be if the temperature of the bridge increases by 35 degrees celsious

    asked on March 1, 2013
  20. @elena

    You helped me with this question earlier today, the answer you got was incorrect, i tried looking through your calculations but i cant find the mistake. the program wont let me see the right answer just tells the answer i put in was wrong. can you please

    asked on April 22, 2012
  21. History

    What do colonialism and imperialism both require

    asked on February 27, 2019
  22. math

    A standard deck of cards has had all the face cards (Jacks, queens, and kings) removed so that only the ace through ten of each suit remains. A game is played in which two cards are drawn (without replacement) from this deck and a six-sided die is rolled.

    asked on February 24, 2011
  23. chemistry

    Your body deals with excess nitrogen by excreting it in the form of urea, NH2CONH2. The reaction producing it is the combination of arginine (C6H14N4O2) with water to give urea and ornithine (C5H12N2O2). C6H14N4O2 + H2O  NH2CONH2 + C5H12N2O2 [Molar

    asked on October 7, 2010
  24. Chem 400

    Direct reaction of solid iodine (I2) and gaseous chlorine (Cl2) produces an iodine chloride,(IxCly), a bright yellow solid. 0.678 g of iodine (I2) is mixed with 0.851 g of chlorine (Cl2). After the elements react, some chlorine is left over along with a

    asked on October 1, 2014
  25. Trigonometry

    Mountain officials want to build a new ski lift from B to C as shown in the figure below. The distance from A to C is 1480 feet. They measure angle DAC to be 32 degrees and angle DBC to be 18 degrees. What is the distance A from to B? Round your answer to

    asked on March 18, 2014
  26. Geometry

    7. What is the surface area of a conical grain storage tank that has a height of 24 meters and a diameter of 16 meters? Round the answer to the nearest square meter. (1 point) 837 square meters 848 square meters 1,991 square meters 1,923 square meters 8.

    asked on January 23, 2017
  27. Physics

    A 55.0kg cheerleader uses an oil-filled hydraulic lift to hold four 130kg football players at a height of 1.20m. If her piston is 19.0cm in diameter, what is the diameter of the football players' piston?

    asked on November 14, 2013
  28. Physics help!!

    A Styrofoam bucket of negligible mass contains 1.60 kg of water and 0.425 kg of ice. More ice, from a refrigerator at -14.8 degree C, is added to the mixture in the bucket, and when thermal equilibrium has been reached, the total mass of ice in the bucket

    asked on April 16, 2012
  29. Physics

    Hi I am absolutely stumped on this question. A loudspeaker is placed between two observers who are 110 m apart, along the line connecting them. If one observer records a sound level of 60.1 dB and the other records a sound level of 74.9 dB, how far is the

    asked on November 28, 2008
  30. phyics

    A 0.20-kg object is attached to the end of an ideal horizontal spring that has a spring constant of 120 N/m. The simple harmonic motion that occurs has a maximum speed of 1.1 m/s. Determine the amplitude A of the motion.

    asked on November 12, 2013
  31. Calculus

    The management of the UNICO department store has decided to enclose an 870 ft2 area outside the building for displaying potted plants and flowers. One side will be formed by the external wall of the store, two sides will be constructed of pine boards, and

    asked on April 13, 2015
  32. physics'

    A 100 kg hoop rolls along a horizontal floor so that the hoop's center of mass has a speed of 0.230 m/s. How much work must be done on the hoop to stop it?

    asked on January 5, 2011
  33. Physics

    Hi I am absolutely stumped on this question. A loudspeaker is placed between two observers who are 110 m apart, along the line connecting them. If one observer records a sound level of 60.1 dB and the other records a sound level of 74.9 dB, how far is the

    asked on November 28, 2008
  34. Calculus

    The volume V of a growing spherical cell is V =4/3πr^3, where the radius is measured in micrometers (1 µm = 10^−6m). Find the average rate of change of V with respect to r when r changes from 3 to each of the following. i)3 to 6µm ii)3 to 4µm

    asked on October 31, 2015
  35. physics

    An automobile traveling at 50.0 km/h has tires of 100.0 cm diameter. (a) What is the angular speed of the tires about their axles? 1 rad/s (b) If the car is brought to a stop uniformly in 25.0 complete turns of the tires (without skidding), what is the

    asked on January 5, 2011
  36. geometry


    asked on June 21, 2016
  37. physics

    A bullet of mass 8 g strikes a ballistic pendulum of mass 2.0 kg. The center of mass of the pendulum rises a vertical distance of 10 cm. Assuming that the bullet remains embedded in the pendulum, calculate the bullet's initial speed.

    asked on December 9, 2010
  38. Physics: Vectors

    A hiker walks 10.0 km[NE], 5.0 km[W], and then 2.0 km[S] in 2.5 h. (a) What is the hiker's displacement? (b) In what direction must the hiker set out, in order to return by the most direct route to the starting point? (c) If the hiker walks at a constant

    asked on June 19, 2012
  39. chemistry

    how many grams of NaOH must be added to 0.250 litres of water to form a solution of PH=10.0?

    asked on September 7, 2010
  40. physics

    The figure below gives the speed v versus time t for a 0.510 kg object of radius 5.90 cm that rolls smoothly down a 30° ramp. What is the rotational inertia of the object? 1 kg·m2

    asked on January 5, 2011
  41. Math

    The cost of admission to the State Fair changed from $8.50 last year to $10.00 this year. Round to the nearest tenth. Show your work a.) What is the percent of change from last year to this year? b.) Is this a percent of increase or decrease? c.) If you

    asked on December 11, 2018
  42. journalism

    You have recently been hired as the news director for a local news station. It’s time to prep for your first newscast. Your newscast will have five blocks and will be 60 minutes long. You need to cover the following in your newscast: Scores from last

    asked on December 3, 2018
  43. Math

    how would you solve this problem? Adult tickets to a play cost $12 and children's tickets cost $5. If 220 tickets were sold and $2542 was collected, how many of each kind of ticket was sold? There are 500 seats in the theater and 280 seats are already

    asked on October 26, 2008
  44. Chemistry

    How many molecules are in 5.2L of carbon dioxide gas?

    asked on July 13, 2016
  45. phyics

    When responding to sound, the human eardrum vibrates about its equilibrium position. Suppose an eardrum is vibrating with an amplitude of 5.0 x10-7 m and a maximum speed of 3.3 x10-3 m/s. (a) What is the frequency (in Hz) of the eardrum's vibrations? (b)

    asked on November 12, 2013
  46. biology

    In guinea pigs, the allele for a rough coat (R) is dominant over the allele for a smooth coat (r). A heterozygous guinae pig (Rr) and a homozygous recessive guinea pig (rr) have a total of nine offspring. The punnett square for this cross shows a 50

    asked on February 27, 2010
  47. American Governent

    1. What type of power does the Constitution grant to the Supreme Court? (1 point) executive power federal power judicial power legislative power 2. Which are examples of judicial restraint in the Supreme Court? Select all that apply. (3 points) The verdict

    asked on December 12, 2016
  48. Statistics

    A local grocery store wants to estimate the mean daily number of gallons of milk sold to customers. Assume the number of gallons sold follows the normal distribution, with a population standard deviation of 5.10 gallons. A random sample of 60 days shows

    asked on October 27, 2013
  49. Pre Calculus

    A cylinder shaped can needs to be constructed to hold 200 cubic centimeters of soup. The material for the sides of the can costs 0.02 cents per square centimeter. The material for the top and bottom of the can need to be thicker, and costs 0.06 cents per

    asked on April 29, 2016
  50. Physics-bobpursleyplease check

    This is the question I posted about two hours ago and I worked it out two ways-could you scroll down and check it, please?If I have a roller coaster, and hill 1 height is 50cm and hill height 2 is 25 cm and the PE is .9 as it approaches the top of hill 2,

    asked on November 4, 2010
  51. Physics

    Hi I am absolutely stumped on this question. A loudspeaker is placed between two observers who are 110 m apart, along the line connecting them. If one observer records a sound level of 60.1 dB and the other records a sound level of 74.9 dB, how far is the

    asked on November 28, 2008
  52. Mathematics

    Does anyone have an idea? A jazz band sells 31 large boxes of fruit and 74 small boxes of fruit for a fundraiser. a. Write and simplify an equation using distributive property to find the profit. b. A large box of fruit costs $9 and a small box of fruit

    asked on November 14, 2017
  53. Math 120

    Write 4logb(X)-1/3logb(y)+2logb(z)as a single logarithm Its log base b.

    asked on December 3, 2014
  54. physics

    A 1000 kg car has four 20 kg wheels. When the car is moving, what fraction of its total kinetic energy is due to rotation of the wheels about their axles? Assume that the wheels have the same rotational inertia as uniform disks of the same mass and size. 1

    asked on January 5, 2011
  55. chem

    A 250 mL sample of oxygen is collected over water at 25 degrees Celcius and 760.0 torr pressure. What is the pressure of the dry gas alone?

    asked on February 2, 2010
  56. Marh

    the volune if a right circular cylinder is 22 cubic what us the volume in cubic cemimters of a rught cubic cylande with twice the radius and half the height

    asked on January 9, 2017
  57. Math-Calc

    Water is leaking out of an inverted conical tank at a rate of 14000.0 cubic centimeters per min at the same time that water is being pumped into the tank at a constant rate. The tank has height 8 meters and the diameter at the top is 6.5 meters. If the

    asked on May 24, 2016
  58. Calculus

    A light is hung 15 ft above a straight horizontal path. If a man 6 ft tall is walking away from the light at the rate of 5 ft/sec, how fast is his shadow lengthening and at what rate is the tip of the man’s shadow moving?

    asked on October 6, 2014
  59. phyics

    An object on a vertical spring oscillates up and down in simple harmonic motion with an angular frequency of 25.1 rad/s. Calculate the distance d by which the spring stretches from its unstrained length when the object is allowed to hang stationary from

    asked on November 12, 2013
  60. physics

    In the figure below, a constant horizontal force !@#$%^&p of magnitude 17 N is applied to a wheel of mass 8 kg and radius 0.70 m. The wheel rolls smoothly on the horizontal surface, and the acceleration of its center of mass has magnitude 0.75 m/s2. (a) In

    asked on January 5, 2011
  61. physics

    A hollow sphere of radius 0.30 m, with rotational inertia I = 0.072 kg m2 about a line through its center of mass, rolls without slipping up a surface inclined at 25° to the horizontal. At a certain initial position, the sphere's total kinetic energy is

    asked on January 5, 2011
  62. calculus

    A car braked at a constant deceleration of 45 ft / s2, producing a skid mark measuring 115 feet before coming to a stop. How fast was the car travelling when the brakes were first applied?

    asked on November 16, 2010
  63. Math

    A woman drove her car on a road running due north at a given rate for 6 hours. She continued her trip on an unsaved road due east for 5 hours at a rate of 4mph slower. Had she been able to go to her destination in a straight line from her starting point

    asked on February 2, 2017
  64. phyics

    An object on a vertical spring oscillates up and down in simple harmonic motion with an angular frequency of 25.1 rad/s. Calculate the distance d by which the spring stretches from its unstrained length when the object is allowed to hang stationary from

    asked on November 12, 2013
  65. trig and geometry

    bernhardt and julia are observing an eagles nest in a tree. Julia is 75m from the tree, and sees it at an angle of elevation of 42 degrees A)How high up the tree is the nest B)Bernhardt is standing 30m behind julia. At what angle of elevation does he see

    asked on March 2, 2012
  66. Math 111

    This is a question that deals specifically with WebWork. Here is the question: Write the set of points from -2 to 4 but excluding -1 and 4 as a union of intervals my solution to this would be: [-2,4]U(-1,4) my reasoning: The first set includes -2 and goes

    asked on September 29, 2011
  67. math

    cindy is making a punch for a party. the recipe calls for 3 bottles of cranberry juice in order to make enought punch to serve 40 guests. how many bottles of cranberry juice wil cindy need in order to make enough punch to serve 100 guest?

    asked on August 9, 2010
  68. math

    according to some student,what is the true purpose homework

    asked on January 23, 2010
  69. math

    In rolling a pair of dice, suppose you win $5 if the sum is 10 but lose $2 if the roll is "doubles." If the price to play is $1, would it be a fair game? Justify your answer.

    asked on October 31, 2008
  70. Algebra

    A ladder is placed against the side of the house. The top of the ladder is 12 ft above the ground. The base wof the ladder is 5feet away from the house. Find the length of the ladde.

    asked on April 4, 2016
  71. Physics

    Hi I am absolutely stumped on this question. A loudspeaker is placed between two observers who are 110 m apart, along the line connecting them. If one observer records a sound level of 60.1 dB and the other records a sound level of 74.9 dB, how far is the

    asked on November 28, 2008
  72. Physics

    A wheel rotating initially at an angular velocity of 1.0 rad/s, accelerates over a 10 S interval at a rate of 0.1 rad/s^2. What angular displacement does the wheel undergo in this 10 S interval, in terms of revolutions?

    asked on November 21, 2016
  73. math

    The volume inside a rectangular storage room is 2,025 cubic feet. The room is 9 feet high. Find the area of the floor.

    asked on April 28, 2015
  74. Chemistry

    Catalytic cracking is an industrial process used to convert high-molecular-mass hydrocarbons to low-molecular-mass hydrocarbons. A petroleum company has a huge supply of heating oil stored as straight chain C17H36, and demand has picked up for shorter

    asked on August 29, 2010
  75. johnglenn

    Discuss some of the advantages to having a cycle that partially replenishes itself. In the Calvin cycle, what would happen to the cycle if there was no carbon dioxide available

    asked on April 23, 2009
  76. phyics

    An object in simple harmonic motion has an amplitude of 0.202 m and an oscillation period of 0.620 s. Determine the maximum speed of the motion

    asked on November 12, 2013
  77. physics

    Two cars both start from rest and have the same constant acceleration. When radar is used to measure the velocity of each car, car A is found to be moving twice as fast as car B. At the instant the radar is used, car A has a displacement that is ______

    asked on September 13, 2010

    A circular curve of highway with radius 200m is designed for traffic moving at 100km/h, and is banked so that cars can make the curve even without friction at that speed. What is the correct angle of banking for this curve? Show steps, please.

    asked on April 19, 2010
  79. Physics!!

    A 4.9 kg bucket of water is raised from a well by a rope. The acceleration of gravity is 9.81 m/s2 . If the upward acceleration of the bucket is 3.3 m/s2, find the force exerted by the rope on the bucket of water. Answer in units of N.

    asked on November 15, 2010
  80. 6th grade math

    Jack went to the store to buy eggs. He thought "i ned enough eggs to last me all week. I eat two eggs for breakfast each day and i need six eggs to give back to my neighbor because i borrowed some." When Jack asked the store clerk for his eggs, he was told

    asked on August 27, 2009
  81. mathemarics

    Given the point m(-3,-4) is the midpoint of XY and that X(7,4)answer the following ; A Find the coordinates of Y . B Find the distance between X and Y ?

    asked on June 27, 2016
  82. Chemistry

    A 0.200 g sample of carbon dioxide, CO2, has a volume of 525 mL and a pressure of 473 mmHg . What is the temperature of the gas in kelvins?

    asked on November 27, 2015
  83. physics

    A bicycle wheel has a diameter of 57.7 cm and a mass of 2.66 kg. The bicycle is placed on a stationary stand and a resistive force of 156 N is applied tangent to the rim of the tire. Assume that the wheel is a hoop with all of the mass concentrated on the

    asked on February 8, 2013
  84. Physics

    Florence who weighs 120lb stands on a bathroom scale in an elevator. What will she see the scale read when the elevator is accelerating upward at 4.0 m/s^2 a) 120lb b) 135lb 3) 105lb d) 90lb

    asked on October 15, 2012
  85. Economics

    A nations capital goods wear out over time, so a portion of it's capital goods become unusable every year. Last year, its residents decided to produce no capital goods, It has experienced no growth in its population or in the amounts of other productive

    asked on June 9, 2010
  86. Social Studies

    I have to write a poem about life in Carribien South America today. But the problem is I can't find any good sources and credible sources, and even if I did have some I don't know how to start writing a poem. Could you give me some sources for it, and an

    asked on May 10, 2018
  87. Physics

    A 1 kg mass attached to a 1 m string is rolled around in a horizontal circular path with an angular velocity of 100 RPM what is the tension of the string? Please show how you got your answer.

    asked on November 21, 2016
  88. Physical

    A motor car travelling at 14m/s on dry flat surface should be able to stop in 14m.Assuming the deceleration to be uniform. Given: its value and the corresponding bracking time is -7m/s^2 , 2 sec Calculate the distance travelled during the first second

    asked on October 22, 2016
  89. physics helpppp!!

    The 2nd harmonic of a string of length 40cm and linear mass density 1.11g.m has the same frequency as the 5th resonance mode of a closed pipe of length 1.4m. Find the tension in the string. use 340 for speed of sound

    asked on February 16, 2012
  90. analytic geometry

    fin the center ,principal axis vertices, sketch the graph of 4x^-y^2 +56 x +2y+195=0

    asked on February 9, 2012
  91. Physics-bobpursley please check

    This is the question I posted about two hours ago and I worked it out two ways-could you scroll down and check it, please?If I have a roller coaster, and hill 1 height is 50cm and hill height 2 is 25 cm and the PE is .9 as it approaches the top of hill 2,

    asked on November 4, 2010
  92. english (gurublue or anyone)

    I'm stumped on what seems to be a fairly easy question that has been asked of me after reading about "Mike Rose". I will summarize the story and provide the question that has given me the mental block. Simple story... Mike Rose as a kid didn't do well in

    asked on February 1, 2009
  93. Pre Calculus

    A piece of cardboard measuring 13 inches by 11 inches is formed into an open-top box by cutting squares with side length x from each corner and folding up the sides. a. Find a formula for the volume of the box in terms of x b. Find the value for x that

    asked on April 29, 2016
  94. Physics

    A 250g wood block firmly attached to a horizontal spring slides along a table with a coefficient of friction of 0.40. A force of 30.N compresses the spring 20cm. If the spring is released from this position what will be the block's speed when it passes

    asked on June 4, 2014
  95. math

    express each answer in exponential form using the indicated bases 4x4x4x4,base 2

    asked on June 25, 2013
  96. English

    How do these develop theme of these allusions from Hamlet? 1. "I would have such a fellow whipped for o'erdoing Termagant" (II,ii,14) So basically Hamlet is telling his actors not over act during the play. 2. “For O, For O, the hobbyhorse is forgot”

    asked on November 11, 2010
  97. Math

    Juan bought 2 tires for his bike. His bike cost $65. How much did he spend on the 2 tires?

    asked on December 8, 2009
  98. Math (Fraction Word Problem)

    You have three-fifths of a pizza leftover, and you plan to eat half of it for lunch. How much of the original pizza do you have left over? If I have 3/5 of a pizza leftover and I plan to eat 1/2 of it for lunch doesn't that mean you have to divide? This is

    asked on October 27, 2016
  99. Physics

    An object with a net charge of 20 µC is placed in a uniform electric field of 627 N/C, directed vertically. What is the mass of the object if it floats in the electric field?

    asked on April 20, 2015
  100. Chemistry 400/ Chem 1A

    Assuming that the resolution of an electron microscope is equal to the deBroglie wavelength of the electrons used, what is the resolution of an electron microscope (in nm) when the electrons are accelerated to a speed of (5.60x10^5) m/s?

    asked on October 29, 2014


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