Most popular questions and responses by a

    Solve each equation by graphing the related function. If the equation has no real-number solution, write no solution. NOTE: when I write + it has a minus on the bottom too x^2+7=0 a. x= +7 b. x = +3.5 c. x= 0 d. no solution *** 3x^2=0 a. +3 b. +1/3 c. 0

    asked on April 4, 2017
  2. statistics

    In the game of​ roulette, a wheel consists of 38 slots numbered​ 0, 00,​ 1, 2,..., 36. To play the​ game, a metal ball is spun around the wheel and is allowed to fall into one of the numbered slots. If the number of the slot the ball falls into

    asked on October 11, 2017
  3. probability

    The lifetime of a type-A bulb is exponentially distributed with parameter λ. The lifetime of a type-B bulb is exponentially distributed with parameter μ, where μ>λ>0. You have a box full of lightbulbs of the same type, and you would like to know

    asked on April 3, 2014
  4. Math

    Write a ratio for the situation in three ways, comparing the first quantity to the second quantity. A zoo has 19 monkeys and 10 chimpanzees. 19 to 10, 19:10, (This) 10 to 29, 10:29, 19 to 29, 19:29, 10 to 19, 10:19, Write three ratios equal to 5/40. 2/14,

    asked on January 10, 2013
  5. Probability

    Let Θ be a Bernoulli random variable that indicates which one of two hypotheses is true, and let P(Θ=1)=p. Under the hypothesis Θ=0, the random variable X is uniformly distributed over the interval [0,1]. Under the alternative hypothesis Θ=1, the PDF

    asked on April 2, 2014
  6. phy

    A blue ball is thrown upward with an initial speed of 20.6 m/s, from a height of 0.8 meters above the ground. 2.5 seconds after the blue ball is thrown, a red ball is thrown down with an initial speed of 8.2 m/s from a height of 23.7 meters above the

    asked on September 13, 2011
  7. Physics

    An arrow is shot from a height of 1.4 m toward a cliff of height H. It is shot with a velocity of 28 m/s at an angle of 60° above the horizontal. It lands on the top edge of the cliff 3.6 s later. a) What is the height of the cliff (in m)? I got 25.191 m

    asked on September 23, 2016
  8. math percent

    Find the percent of markup. Round to the nearest tenth $31.00 to $35.00

    asked on December 18, 2015
  9. Probability

    The random variable X is uniformly distributed over the interval [θ,2θ]. The parameter θ is unknown and is modeled as the value of a continuous random variable Θ, uniformly distributed between zero and one. Given an observation x of X, find the

    asked on April 3, 2014
  10. Probability

    A defective coin minting machine produces coins whose probability of Heads is a random variable Q with PDF fQ(q)={3q2,0,if q∈[0,1],otherwise. A coin produced by this machine is tossed repeatedly, with successive tosses assumed to be independent. Let A be

    asked on April 2, 2014
  11. Probability

    Alice has two coins. The probability of Heads for the first coin is 1/3, and the probability of Heads for the second is 2/3. Other than this difference, the coins are indistinguishable. Alice chooses one of the coins at random and sends it to Bob. The

    asked on April 2, 2014
  12. SS

    The political movement that brought Africans together in the 1950s was known as ________. a. imperialism b. salt trade c. colonialism d. Pan-Africanism Enslaved Africans from West Africa traveled across the Atlantic Ocean to European Colonies in the

    asked on September 29, 2013
  13. Probability

    We have k coins. The probability of Heads is the same for each coin and is the realized value q of a random variable Q that is uniformly distributed on [0,1]. We assume that conditioned on Q=q, all coin tosses are independent. Let Ti be the number of

    asked on April 3, 2014
  14. probability

    The vertical coordinate (“height") of an object in free fall is described by an equation of the form x(t)=θ0+θ1t+θ2t2, where θ0, θ1, and θ2 are some parameters and t stands for time. At certain times t1,…,tn, we make noisy observations Y1,…,Yn,

    asked on April 2, 2014
  15. Probability

    Let U, V, and W be independent standard normal random variables (that is, independent normal random variables, each with mean 0 and variance 1), and let X=3U+4V and Y=U+W. Give a numerical answer for each part below. You may want to refer to the standard

    asked on April 20, 2014
  16. math

    A parking lot space is in the shape of a rectangle. If the space has a length of 23 feet and a width of 12 feet, what is the area of the parking space?

    asked on February 14, 2018
  17. Probability

    Let X=U+W with E[U]=m, var(U)=v, E[W]=0, and var(W)=h. Assume that U and W are independent. The LLMS estimator of U based on X is of the form U^=a+bX. Find a and b. Express your answers in terms of m, v, and h using standard notation. a=- unanswered b=-

    asked on April 3, 2014
  18. physics

    Two cars start from rest at a red stop light. When the light turns green, both cars accelerate forward. The blue car accelerates uniformly at a rate of 4.6 m/s2 for 4.4 seconds. It then continues at a constant speed for 8.5 seconds, before applying the

    asked on September 13, 2011
  19. math

    A hot water heater measures 20" in diameter. What is the area of a metal base for the water heater, assuming a four-inch overhang for the base beyond the edge of the heater? (Round to the nearest tenth.)

    asked on May 28, 2013
  20. Life Span Development

    1. Levels of social cognitive __________ do not always match __________. A. reasoning / behavior B. attributions / behavior C. behavior / biases D. attributions / reasoning

    asked on January 6, 2017
  21. calculus2

    A tank is full of water. Find the work required to pump the water out of the spout. (Use 9.8 m/s^2 for g. Use 1000 kg/m^3 as the density of water. Assume r = 9 m and h = 3 m.) The tank is a spherical shape with r as the radius(9m). On top of the tank is a

    asked on June 28, 2018
  22. Probability

    Let N be a geometric r.v. with mean 1/p; let A1,A2,… be a sequence of i.i.d. random variables, all independent of N, with mean 1 and variance 1; let B1,B2,… be another sequence of i.i.d. random variable, all independent of N and of A1,A2,…, also with

    asked on April 3, 2014
  23. Probability

    Consider a Poisson process with rate λ. Let N be the number of arrivals in (0,t] and M be the number of arrivals in (0,t+s], where t>0,s≥0. In each part below, your answers will be algebraic expressions in terms of λ,t,s,m and/or n. Enter 'lambda' for

    asked on May 1, 2014
  24. la

    chose the meaning that best matches the word in italics. many actors avoid playing superheroes because they fear the ********stereotype******** that comes with success in the role. a label b popularity c persona d restrictions

    asked on December 22, 2015
  25. Calculus

    Find the surface area of the part of the sphere x2+y2+z2=81 that lies above the cone z=√(x2+y2)

    asked on December 6, 2015
  26. Calculus

    The total stopping distance T of a vehicle is shown below, where T is in feet and x is the speed in miles per hour. T = 2.5x + 0.5x^2 Approximate the change and percent change in total stopping distance as speed changes from x = 15 to x = 18 miles per

    asked on March 3, 2018
  27. Probability

    Let T1,T2,…,Tn be i.i.d. observations, each drawn from a common normal distribution with mean zero. With probability 1/2 this normal distribution has variance 1, and with probability 1/2 it has variance 4. Based on the observed values t1,t2,…,tn, we

    asked on April 2, 2014
  28. Probability

    For each of the following sequences, determine the value to which it converges in probability. (a) Let X1,X2,… be independent continuous random variables, each uniformly distributed between −1 and 1. Let Ui=X1+X2+⋯+Xii,i=1,2,…. What value does the

    asked on April 23, 2014
  29. physics

    An electron experiences an electric force of 0.70 nN . What’s the field strength at its location?

    asked on March 3, 2018
  30. Probability

    For any given flight, an airline tries to sell as many tickets as possible. Suppose that on average, 10% of ticket holders fail to show up, all independent of one another. Knowing this, an airline will sell more tickets than there are seats available

    asked on April 23, 2014
  31. Math

    Yin's cellphone plan costs $30 a month. She used 12.5 hours in May. What was her cost per minute? About how many call can she make? Yin's average call lasted 3.25 minutes. How much did an average call cost?

    asked on January 29, 2016
  32. Statistics

    Problem 6 A histogram shows the number of hours students spent preparing for a test. The table below gives the intervals and the heights of the bars (in percent per hour). Intervals contain the left endpoint but not the right. No student spent 25 hours or

    asked on February 25, 2013
  33. Social Studies

    Compare and contrast the treatment of different religions by rulers of the Arab empire.

    asked on January 24, 2019
  34. Calculus

    Sketch the vector field F⃗ (r⃗ )=2r⃗ in the plane, where r⃗ =⟨x,y⟩. Select all that apply. A.All the vectors point away from the origin. B. The vectors increase in length as you move away from the origin. C. All the vectors point toward the

    asked on October 10, 2015
  35. Calculus

    For the vector field G⃗ =(yexy+3cos(3x+y))i⃗ +(xexy+cos(3x+y))j⃗ , find the line integral of G⃗ along the curve C from the origin along the x-axis to the point (3,0) and then counterclockwise around the circumference of the circle x2+y2=9 to the

    asked on November 20, 2015
  36. Probability

    We are given the following statistics about the number of children in the families of a small village. There are 100 families: 10 families have no children, 40 families have 1 child each, 30 families have 2 children each, 10 families have 3 each, and 10

    asked on May 1, 2014
  37. physics

    he index of refraction of crown glass is 1.53 for violet light, and it is 1.51 for red light. (a) What is the speed of violet light in crown glass? (b) What is the speed of red light in crown glass?

    asked on May 14, 2013
  38. college physics

    If the amplitude of a sound wave is tripled, A.) by what factor will the intensity increase? B.) by how many dB will the sound level increase?

    asked on May 6, 2010
  39. physics

    A white-crowned sparrow flying horizontally with a speed of 1.65 m/s folds its wings and begins to drop in free fall. (a) How far does the sparrow fall after traveling a horizontal distance of 0.550 m? (b) If the sparrow's initial speed is increased, does

    asked on April 18, 2012
  40. math

    An object is launched at 19.6 m/s from a 58.8 m tall platform. The equation for the object's height above the ground (y) at time tseconds is y = –4.9t2 + 19.6t + 58.8 Use the quadratic formula to find the roots of this equation. What do these numbers

    asked on March 6, 2019
  41. math

    A man makes a simple discount note with a face value of $2,200, a term of 140 days, and a 9% discount rate. Find the discount.

    asked on May 16, 2015
  42. Physics

    Similarities between distance and displacement similarities between speed and velocity

    asked on February 18, 2014
  43. chemistry

    A 8.50-g sample of solid AlCl3·6H2O was heated such that the water turned to steam and was driven off. Assuming ideal behavior, what volume would that steam occupy at 1.00 atm and 100.0 °C?

    asked on September 27, 2014
  44. math

    d = 0.08t^2 - 1.6t + 9 A student stands facing a motion detector. He quickly walks toward the detector, slows down, stops and then slowly walks away from the detector. He speeds up as he gets farther away from the detector. When is the student closest to

    asked on March 7, 2019
  45. math

    the amount of jens month phone bill is normally distributed with a mean of $69 and a standard deviation of $10. what is 68.26% of phone bill between?

    asked on December 3, 2015
  46. la

    The speaker in "Birches" compares the boy's climbing to a. girls dying there hair b. sweeping up broken glass c. a forest full of spiderwebs d. filling a cup to the top I think D

    asked on September 17, 2017
  47. Trigonometry

    Point P is located at the intersection of the unit circle and the terminal side of angle theta in standard position. Find the coordinates of P to the nearest thousandth. theta = -105degrees Please explain the steps. I'm completely stuck.

    asked on June 1, 2017
  48. calculus2

    A manufacturer of corrugated metal roofing wants to produce panels that are u = 48 in. wide and 2 in. thick by processing flat sheets of metal as shown in the figure. The profile of the roofing takes the shape of a sine wave with equation y = sin(πx/12).

    asked on July 21, 2018
  49. Probability

    In parts 1, 3, 4, and 5 below, your answers will be algebraic expressions. Enter 'lambda' for λ and 'mu' for μ. Follow standard notation. Shuttles bound for Boston depart from New York every hour on the hour (e.g., at exactly one o'clock, two o'clock,

    asked on April 30, 2014
  50. AlgebraII

    A bag contains 5 pictures of Paris and 7 pictures of London. Determine whether the events of selecting the picture of London and another picture of London with replacement is independent or dependent. Then identify the indicated probability.

    asked on April 9, 2012
  51. math

    For what value of k does the equation x2 + kx + 9have: Two distinct real roots One real root No real root

    asked on March 6, 2019
  52. Probability

    Let Θ be an unknown random variable that we wish to estimate. It has a prior distribution with mean 1 and variance 2. Let W be a noise term, another unknown random variable with mean 3 and variance 5. Assume that Θ and W are independent. We have two

    asked on April 20, 2014
  53. Social Studies

    How did the end of world war 2 impact Minnesota's economy? How did the GI Bill help encourage economic growth in Minnesota and the rest pf the naiton? How are the growth of highways and suburbs related?

    asked on April 30, 2018
  54. J

    the decimal expansion of 147/120 will be terminate after how many decimal

    asked on September 12, 2016
  55. Chem

    A dilute aqueous solution of Na2SO4 is electrolyzed between Pt electrodes for 3.70 h with a current of 2.77 A . Part A What volume of gas, saturated with water vapor at 25∘C and at a total pressure of 742 mmHg , would be collected at the anode? The vapor

    asked on March 31, 2018
  56. Math

    In an examination of a certain class, at least 70% of the students failed in Physics, at least 72% failed in Chemistry, at least 80% failed in Mathematics and at least 85% failed in English. How many at lest must have failed in all the four subjects ?

    asked on May 26, 2017
  57. Geometry Ratios

    At the half time show during a football game, a marching band is to form a rectangle 50yards by 16yards. The conductor wants to plan out the band members positions using a 14- by 8.5-in. sheet of paper. What scale should she use to fir both dimensions of

    asked on March 13, 2012
  58. chemistry

    What is the Na+ concentration of 2.85 M sodium sulfate?

    asked on October 10, 2010
  59. chemistry

    Hydrogen gas produced by this reaction is typically collected via water displacement, during which time the hydrogen gas becomes saturated with water vapor. If 238.4 mL of gas with a total pressure 1.27 atm was collected via water displacement at 29.4 °C,

    asked on September 27, 2014
  60. chemistry

    Air is 78.1% nitrogen, 20.9% oxygen, and 0.934% argon by moles. What is the density of air at 22 °C and 760 torr? Assume ideal behavior.

    asked on September 27, 2014
  61. Algebra2

    how do you solve this? A dice is rolled twice. What is the probability of getting a multiple of 3 on the first roll or a total of 7?

    asked on April 10, 2012
  62. math

    The graph of y = –3sin (2x) is shifted to the left by 30° units and up 5 units. Write the new equation. My answer y= -3sin (2x- 30°) +5 Is this correct?

    asked on April 15, 2019
  63. chemistry

    Imagine there is a tank of unknown gas that contains 53.31% carbon, 35.51% oxygen, and 11.18% hydrogen by mass. At 35.0 °C and 0.470 bar, 2.0 L of the gas has a mass of 3.3 g. Using this information, answer the following questions. a.) What is the

    asked on September 27, 2014
  64. Math

    What is the simplified version of this expression 28st/-4t the / meaning its a fraction

    asked on September 21, 2018
  65. History

    What impact did imperial Spain have on the Americas? Spanish culture came to dominate and replace native cultures. Local leaders were replaced by Spanish parliamentary assemblies. Financing from Spain started the industrialization of the Americas.

    asked on August 3, 2018
  66. physics

    an 85.0kg mountaineer remains in equilibrium while climbing a vertical cliff. the tension force in the supporting rope is 745 N. Find the magnitude of the reaction force F, which the cliff exerts on the mountaineer's feet.

    asked on October 3, 2017
  67. Business Math - help needed

    Federal Express bought material handling equipment for its hub operations that cost $180,000. Using the MACRS, what is the depreciation expense in year 3 (using a five-year class)? A. $43,560 B. $34,560 C. $15,360 D. $40,000 Answer: B??

    asked on April 10, 2016
  68. math

    a man gets an invoice for $460 with terms 2/10, 1/15, n28 ow much would he pay 25 after the invoice date? help a little confused?

    asked on April 22, 2015
  69. calculus

    A small aircraft, on a heading of 225 degrees, is cruising at 150 km/h. It is encountering a wind blowing from a bearing of 315 degrees at 35 km/h. Determine the aircraft's ground velocity.

    asked on May 2, 2010
  70. Chemistry

    In a gaseous system at equilibrium with its surroundings, as molecules of A(g) collide with molecules of B(g) without reacting, the total energy of the gaseious system 1. decreases 2. increases 3. remains the same

    asked on April 13, 2009
  71. Managerial Economics

    Economists consider which of the following costs to be irrelevant to a short run business decision? A)out of pocket B)historical cost C)opportunity cost D)replacement cost

    asked on November 12, 2007
  72. chemistry

    Ka for hypochlorous acid, HClO, is 3.0*10^(-8). Calculate the pH after 10.0, 20.0, 30.0, and 40.0 mL of 0.100M NaOH have been added to 40.00mL of 0.100M HClO.

    asked on March 10, 2011
  73. Managerial Economics

    Diseconomies of scale can be caused by: A)bureaucratic inefficiencies B)increasing advertising and promotional costs. C)the law of diminishing returns D)all of the above

    asked on November 12, 2007
  74. physics

    A child of mass 54.7 kg sits on the edge of a merry-go-round with radius 2.3 m and moment of inertia 222.81 kgm2. The merrygo-round rotates with an angular velocity of 1.6 rad/s. What radial force does the child have to exert to stay on the merry-go-round?

    asked on March 29, 2016
  75. English

    If you guys were trying to survive the Titanic How do you think you would feel? How would you react? What would you do to secure your survival?

    asked on January 14, 2019
  76. Probability

    A single dot is placed on a very long length of yarn at the textile mill. The yarn is then cut into pieces. The lengths of the different pieces are independent, and the length of each piece is distributed according to the same PDF fX(x). Let R be the

    asked on May 1, 2014
  77. Science

    Acetaldehyde, CH3CHO, will decompose into methane and carbon monoxide according to CH3CHO (g) -> CH4 (g) + CO (g) At 450C the rate of consumption of CH3CHO is measured to vary with the concetration of CH3CHO raised to the power 1.5. With a CH3CHO

    asked on April 28, 2013
  78. Chemistry

    For ethanol, C2H5OH, which is mixed with gasoline to make the fuel gasohol, H°f = -277.63 kJ/mol. Based upon data in Table 6.2, and that the density of ethanol is 0.787 g•cm-3, the number of kilojoules released by burning completely 2.40 gallons of

    asked on October 16, 2011

    A 2000kg elevator is attached to a 1800kg counterweight. What power must the motor supply to raise the elevator at 0.4m/s?

    asked on April 12, 2016
  80. Calculus

    A company manufactures x units of one item and y units of another. The total cost in dollars, C, of producing these two items is approximated by the function C=7x^2+xy+1y^2+600. A) If the production quota for the total number of items (both types combined)

    asked on October 18, 2015
  81. physics

    The drawing below shows a person who, starting from rest at the top of a cliff, swings down at the end of a rope, releases it, and falls into the water below. There are two paths by which the person can enter the water. Suppose he enters the water at a

    asked on February 22, 2013
  82. science

    A small hockey puck slides without friction over the icy hill and lands 6.20 m from the foot of the cliff with no air resistance.What is its initial speed v0 at the bottom of the hill?

    asked on September 27, 2012
  83. math

    Find the domain and range of the function y= -3(x-1/3)^2+4/3

    asked on March 4, 2019
  84. trig

    Describe how the graphs of y + 3 = 2sin (3x + 90°) compares to the graph of y = sin (x).

    asked on April 16, 2019
  85. Civics

    In what way do mixed and market economies support the ideals of democracy? A. Mixed and market economies elect a few farmers and local leaders to choose which goods and services to produce. B. Mixed and market economies do not produce more goods or

    asked on May 19, 2016
  86. Probability

    All ships travel at the same speed through a wide canal. Each ship takes t days to traverse the length of the canal. Eastbound ships (i.e., ships traveling east) arrive as a Poisson process with an arrival rate of λE ships per day. Westbound ships (i.e.,

    asked on April 30, 2014
  87. Physics Help Please

    A sample of an unknown material appears to weigh 270 N in air and 165 N when immersed in alcohol of specific gravity 0.700. (a) What is the volume of the material? (b) What is the density of the material?

    asked on November 12, 2010
  88. math

    Is my answer correct? Write this quadratic function in the vertex form y = 4(x+5)(x-2) = 4(x² + 3x - 10) = 4(x² + 3x + 9/4 - 10 - 9/4) = 4(x² + 3x + 9/4) - 49 = 4(x+3/2)² - 49 Ans: y = 4(x+3/2)² - 49 Vertex = (-3/2, -49)

    asked on March 4, 2019
  89. Trig/pre-calc

    r=8cos(theta)+5sin(theta), convert the polar equation into a rectangular equation and then complete the square and determine the center radius...? Help?! I missed the section, and am not getting anywhere with the text...

    asked on August 12, 2011
  90. math

    D = 0.08t^2 - 1.6t + 9 Why does this equation above fits this model: A student stands facing a motion detector. He quickly walks toward the detector, slows down, stops and then slowly walks away from the detector. He speeds up as he gets farther away from

    asked on March 7, 2019
  91. Math

    -4/10x -9 < 9/10 = x < 24 3/4 Did I do this right? was solving for the inequality and the -4/10x is together.

    asked on November 1, 2018
  92. Civics

    Pedro is thinking about buying U.S. savings bonds. However, there is a financial institution controlled by the government that may actively discourage Pedro from buying bonds. How and why would such a financial institution do this? A. Stocks on Wall Street

    asked on May 19, 2016
  93. Probability

    Suppose that you have two laptops, both of which you begin using at time 0. Each laptop will eventually fail, and we model each one's lifetime as exponentially distributed with the same parameter λ. The lifetimes of the two laptops are independent. One of

    asked on April 30, 2014

    A 320-N sphere 0.20 m in radius rolls without slipping 6.0 m down a ramp that is inclined at 25° with the horizontal. What is the angular speed of the sphere at the bottom of the slope if it starts from rest?

    asked on November 3, 2010
  95. politics

    Why is free health care important in a democratic society?

    asked on February 28, 2019
  96. Math

    Simplify, stating any restrictions on the variables: a. 18a^6bc^7d^3/ 12a^2b^4c^7d b.x^2+5x+6/x^2-2x-15 c. 6y^2-96/2y^2+18y+40

    asked on February 22, 2019
  97. chem TITRATION

    1. If a student fails to remove a large air bubble in the buret before beginning the titration, what will be the effect on the volume of titrant required to reach the titration endpoint? A. The student will record a volume that is SMALLER than it should be

    asked on May 25, 2018
  98. math

    Write this equation in the vertex form: y= -3x^+2x+1

    asked on March 2, 2019
  99. math

    a man holds a note of $6,000 that has an interest rate of 13% annually the note was made on march 17 and is due november 11 he sells the note to a bank on june 14 at a discount rate of 12% annually find the proceeds on the third-party discount rate. Ok now

    asked on May 16, 2015
  100. Probability

    Let X be a continuous random variable. We know that it takes values between 0 and 3, but we do not know its distribution or its mean and variance. We are interested in estimating the mean of X, which we denote by h. We will use 1.5 as a conservative value

    asked on April 23, 2014


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