Questions and answers by visitors named Ray


  1. A car was valued at $38,000 in the year 2003. The value depreciated to $11,000 by the year 2009. Assume that the car value continues to drop by the same percentage.

    -What will the value be in the year 2013?

  2. What is the limit of g(x)=x as x approaches pi?

    Would it just be pi??

  3. 1.630 g of iron ore is dissolved in an acidic solution. This solution is titrated to a pink endpoint with 27.15 mL of a 0.020 M KMnO4 solution.

    a. How many moles of MnO4- ions were consumed? b. How many moles of Fe2+ were in the iron ore sample? c. What is

  4. A company introduces a new product for which the number of units sold S is given by the equation below, where t is the time in months.

    s(t)=155(7-9/(2+t)) a) Find the average rate of change of s(t) during the first year. Which my answer was 1395/28 b)

  5. 1. Three resistors are placed in series. They have the following resistances: R1 = 20 ohms, R2 = 20 ohms, R3 = 10 ohms. What current would be moved through this circuit by a 5-V power supply?

    A. 1.0 A B. 0.10 A C. 25 A D. 250 A 2. Two resistors are placed

  6. What is the difference between class limits and class boundaries?

    A) Class limits are the numbers that separate classes without forming gaps between them. Class boundaries are the least and greatest numbers that can belong to the class. For integer data,

  7. In how many different ways can six of ten people be seated

    in a row of six chairs? I don't have the answer, but from my rough understanding of permutations and combinations, I got: 10C6 * 6! = 210 * 6! I figure first 6 people have to be chosen out of the

  8. Jerry is packing cylindrical cans with diameter 6 in. and height 10 in. tightly into a box that measures 3 ft by 2 ft by 1 ft. All rows must contain the same number of cans. The cans can touch each other. He then fills all the empty space in the box with

  9. A truck with 40-in.-diameter wheels is traveling at 50 mi/h.

    a) Find the angular speed of the wheels in rad/min b) How many revolutions per minute do the wheels make?

  10. Object A is moving due east, while object B is moving due north. They collide and stick together in a completely inelastic collision. Momentum is conserved. Object A has a mass of mA = 17.5 kg and an initial velocity of = 8.50 m/s, due east. Object B,

  11. Evaluate the expression without using a calculator (Make a sketch of a right triangle)

    tan(arccot 2) Thanks in advance! I'm trying to refresh my memory of these kinds of problems and I'm having trouble on how to solve this problem

  12. A car rental agency advertised renting a car for $24.95 per day and $0.33 per mile.If David rents this car for 3 days, how many whole miles can he drive on a $100 budget?

  13. The parachute on a race car of weight 8,810 N opens at the end of a quarter-mile run when the car is traveling at 34 m/s. What total retarding force must be supplied by the parachute to stop the car in a distance of 1,100 m?

  14. You are given a vector in the xy plane that has a magnitude of 70.0 units and a y component of -55.0 units. What are the two possibilites for its x component? Please explain, thanks! :)

  15. A solution of HNO3 has a pH of 4.5, What is the molarity of HNo3?

  16. Which statement correctly contrasts Mary Ludwig Hayes contribution during the revolution to those of Betsy Ross

  17. My outer shell has two electrons and I'm in the fourth period

  18. How do I solve 30.0L x 10 mol/L ? I couldn't find a similar practice question in my textbook, so I'm not sure what steps to take.

  19. A fixed mass of a certain gas has a volume of 96cm at 67 degrees Celsius and 700mmHg .Find the volume the gas would occupy at s.t.p

  20. Functions that are smaller than 1/4

  21. A starigh line passes through the point (8,-2) and (4,-4)write it equation in the form of ax ,+by+c =0where a,b and c are integers

  22. A large electronic retailer has been selling digital cameras for $840 each. At this price the store sells 120 per month. They determine that for every $10 discount in price, the number of sales increases by 5 each month.

  23. The dimensions of a rectangular prism are shown below:

    Length: 1 and 1 over 3 feet Width: 1 foot Height: 2 and 1 over 3feet The lengths of the sides of a small cube are 1 over 3 foot each. Part A: How many small cubes can be packed in the rectangular prism?

  24. Pulleys and Inclined Planes Quick Check

  25. A book of 100 pages is flipped open. The sum of the facing numbers can be divided by 5. The quotient is a product of 3 and 7. What are the facing page numbers

  26. Lysine is a compound composed of carbon, hydrogen, nitrogen and oxygen. When 1.50 g of

    lysine is burned, 2.72 g of carbon dioxide, 1.29 g of water and 0.287 g of nitrogen gas are produced. What is the empirical formula of lysine? If the molar mass of lysine

  27. At a farm, there are some cows and some chickens. The number of chickens is 3 times the number of cows. If the animals have a total of 110 legs, how many cows are there?

  28. At a farm, there are some cows and some chickens. The number of chickens is 3 times the number of cows.

    If the animals have a total of 110 legs, how many cows are there?

  29. If f(x) is an odd function, which function must also be odd? Explain.

    (1) f(x – 1) + 5 (2) 2f(x) + 3 (3) 1/2f(x) (4) f(x – 4)

  30. The fountain is made up of two semicircles, the 2 semicircles have a radius of 10ft, and a quarter circle. Find the perimeter and the area of the fountain. Round the perimeter to the nearest tenth of a foot and the area to the nearest square foot.

  31. how many grams of ice at 0c could be melted by the addition of 0.400kj of heat

  32. Economics Basics Practice

    1. How does scarcity affect producers? (1 point) Review Guidelines: If you guessed the answer to this question, or did not answer it correctly, go back and review scarcity in Scarcity and Choice. Unselected answer (0 pts) Limited

  33. what was the the native Americans experiences on encomienda land

  34. In a survey of 290 newspaper readers

  35. The drama teacher wants to estimate how many tickets to sell for a show.

    The auditorium has 56 rows of seats. There are 32 seats in each row. Which explains whether it makes more sense to find an overestimate or an underestimate to decide how many tickets

  36. A cord with two masses at each end (Mass 1 = 6.0 kg and Mass 2 = 11 kg) is hanging by a pulley.

    1) Calculate the acceleration of the system. 2) Calculate the tension force on the cord.

  37. What is the period of y=5sin1/3(x+25°)-4

  38. What is the phase shift of y=5sin1/3(x+25°)-4

  39. What is the density of g/cm^3, of a piece of metal that has a mass of. 500kg and a volume of 63cm^3

  40. In a previous​ poll, 31​% of adults with children under the age of 18 reported that their family ate dinner together seven nights a week. Suppose​ that, in a more recent​ poll, 327 of 1114 adults with children under the age of 18 reported that

  41. Hi i forgot how to do this please help!

    Find the​ t-value such that the area left of the​ t-value is 0.1 with 21 degrees of freedom.

  42. Determine the sample size required to estimate the mean score on a standardized test within 44 points of the true mean with 9999​% confidence. Assume that sequals=1313 based on earlier studies.

  43. In a college student​ poll, it is of interest to estimate the proportion p of students in favor of changing from a​ quarter-system to a​ semester-system. How many students should be polled so that p can be estimated to within 0.09 using a​ 99%

  44. Hello please help..

    The owner of a computer repair shop has determined that their daily revenue has mean​ $7200 and standard deviation​ $1200. The daily revenue totals for the next 30 days will be monitored. What is the probability that the mean daily

  45. A simple random sample of size n equals=3737 is obtained from a population with μ equals=6969 and σ equals=1515.

    ​(a) What must be true regarding the distribution of the population in order to use the normal model to compute probabilities involving the

  46. (7.5x10^3) ÷ (1.5x10^4)

  47. what volume of 0.5m BaCl 2 is needed to have 0.1 moles of BaCl 2 ?

  48. The boy whose mother died is

    around.What is the grammatical name and function.

  49. Which theory might explain why people claim immigrants for the countries troubles even though there’s no evidence for this

  50. Suppose the force of kinetic friction on a sliding block of mass m is 2.5 N [backward]. What is the force of kinetic friction on the block if another block of mass 2m is placed on its upper surface?

  51. A tractor and tow truck have rubber tires on

    wet concrete. The tow truck drags the tractor at constant velocity while its brakes are locked. If the tow truck exerts a horizontal force of 1.0 x 10^4 N on the tractor, determine the mass of the tractor. Refer

  52. To minimize the cost of producing a given quantity of output, the input bundle must be chosen so that the marginal products of all inputs are identical. True or false?

  53. liquid hexane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water. Suppose 7.8 g of hexane is mixed with 48.4 g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction.

  54. Solve the system by graphing. (Enter your answers as a comma-separated list. If the system is inconsistent, enter INCONSISTENT. If the system is dependent, enter DEPENDENT.)

    x + y = 4 x − y = 2 (x, y) =

  55. A football is kicked at an angle of 45° to the horizontal over a defence line up with a velocity of 15m/s. Calculate the magnitude of the horizontal velocity of the ball at its highest point neglecting friction

  56. help please!! write an equation of a parabola with vertex at the origin and the given focus

    focus at (2,6)??? Please help im lost!!

  57. Consider the the distribution of under-inflated tires on a four-wheel automobile. The mass

    density is given by: p(0) = 0.4, p(1) = p(2) = p(3) = 0.1, p(4) = 0.3 a) Find the expected value and the variance of this distribution. b) For what proportion of such

  58. The dimerization of butadiene is a second order reaction process. In an experiment a sample of 0.0087 mol of butadiene was heated in a liter flask. After 600 seconds 21% of the butadiene has dimerized. Calculate the rate constant.

  59. What happened to airplane manufacturing after World War II?

    1 Airplane manufacturers began producing goods for the oil industry. 2 Airplane manufacturing rebounded and produced airplanes, parts, and equipment. 3 Airplane manufacturing decreased in Texas as

  60. How were prisoner of war camps different from internment camps?

    1 Prisoner of war camps held fewer people than internment camps. 2 Prisoner of war camps held captured soldiers. 3 There was more freedom in prisoner of war camps. 4 Prisoner of war camps were

  61. Egg-laying land animals have evolved to produce eggs with tough shells to ensure that

    1 external fertilization can take place. 2 the egg and sperm can fuse 3 parental care is unnecessary*** 4 the developing embryo does no dry out

  62. A man with a genetic disease marries a woman who does not carry the disease. It is not possible for their sons to have the disease. The disease must be

    X-linked dominat Y-linked dominat X-linked reccesive Y-linked reccesive I'm reposting this because i

  63. X-linked dominant

    Y-linked dominant X-linked recessive Y-linked recessive

  64. how did the decade of prosperity affect the lives of many Mexican-Americans in Texas

    They became wealthier They became migrant laborers They Moved to other states They Entered New Industries My answer is the 3rd one please check that for me!

  65. what efforts did james hogg make to fix the corporate world in Texas?

    1 allowed railroads to choose the path of the rail lines 2 created laws against monopolies 3 made his own insurance company 4 made it easier to start companies

  66. I am given a vector function <2cos(t) + cos(2t), 2sin(t) + sin(2t), 0>

    (in other words) : (2cos(t) + cos(2t))i + (2sin(t) + sin(2t)j + 0k Compute the slope dy/dx and concavity d^2x/(dx^2) at t = pi/3. I understand that finding the slope of a vector is

  67. Compute the area of the parallelogram formed by A(-2, 1, 4), B(0, -2, 3) C(-1, 6, 5), and D(1, 3, 4).

    So for this problem, do I turn the four points into two vectors with AD and BC and then take the cross product and then find the magnitude? Taking the

  68. Was wondering, anyone here know discrete math? Specifically regarding to rules of inferences?

  69. Given the equation x + z = 2.

    Is P parallel to any of the coordinate planes? Is P perpendicular to any of the coordinate planes?

  70. If two cars started out at the same spot and traveled in opposite directions for 90 minutes at 60miles per hour -far apart in total miles would they be at the end of the 90 minutes?

  71. I am trying to prepare for my finals and I'm approached with this question where I'm not entirely clear what the answer should be:

    Given the function h(t) graphed below, define A(x) = ∫[-0.5,x] h(t) dt . (Graph is in the link)

  72. I'm given the equation S = L(1 - e^(-kt))

    I am asked to write S as a function of t when L = 100, S = 25 when t = 2 So would my final answer just have S and t as variables? Or have S, t and L as variables? Ended up with S = 100(1 - e^((ln(3/4)/2)*t) Or is

  73. The rate of change in the number of miles s of road cleared per hour by a snowplow is inversely proportional to the depth h of snow. That is,

    ds/dh = k/h Find s as a function of h given that s = 25 miles when h = 3 inches and s = 10 miles when h = 9 inches

  74. Some of the curves corresponding to different values of C in the general solution of the differential equation are shown in the graph. Find the particular solution that passes through the point (0, 2).

    y(x^2+y) = C 2xy + (x^2+2y)y' = 0 How would I start

  75. Take the area enclosed by the curves y = sqrt(x), y = 1, and x = 4. Rotate it around the line x = 5. Find the volume.

    While I understand the general problem would call for the shell method ∫[a,b] 2*pi*r*h dx With r = 5 - x and h = sqrt(x) - 1 But, what

  76. Since sec^2θ - 1 = tan^2θ

    I know this is trivial, but I want to make sure I'm doing this right before I apply it to the integral I'm trying to solve... If I have some constant a, (a^2secθ)^2 - (a^2)^2 If I wanted to change this to tan would it be:

  77. I'm having trouble trying to solve for the partial fraction decomposition in order to find the integral.

    ∫ x / (x^4 - a^4) dx I'm assuming a is some constant in this case. So I factored the denominator to this: (x^4 - a^4) = (x^2 + a^2)(x + a)(x - a)

  78. I am trying to understand my teacher's example of a Work problem.

    Cut to the chase here's a picture of the problem: goo.gl/photos/AqZ6ENmHLg6heixD7 While I understand how to integrate fairly well, I'm still confused on how exactly my teacher set up the work

  79. I am supposed to find the area of the region given two boundaries and two functions revolving about the x axis.

    x = 0 x = pi/2 y = cos(x/2) y = sin(x/2) Graphing those two functions made me select to use the washer method. Therefore, I set my definite

  80. Find ∫1/((x^2+5)^(3/2)) dx

    I figured this would be a trig substitution problem, so I set x = sqrt(5)tanθ and dx = sqrt(5)sec^2(θ) dθ This would lead to: ∫(sqrt(5)sec^2(θ)) / (5tan^2(θ) + 5)^(3/2) dθ But I'm kinda lost on what to do next. I'm used

  81. I would like to solve the ∫sin^2(pix) dx

    Using the given substitution identity: sin^2(x) = (1/2)(1-cos2x) This is what I did so far: ∫sin^2(pix) let u = pix du = pi dx (1/pi)∫sin^2(u)du Applying the identity is where I'm lost on how to continue

  82. ∫sin(x)cos(x) dx

    Using the identity sin(2x) = 2 sin(x) cos(x)?

  83. I am given an integral to solve with given substitution values. I got an answer, but I'm not quite sure if it's correct as an online integral calculator gave a different answer.

    ∫ x sqrt(4-x) dx Given that u = 4-x . In this case, x = 4 - u du = -dx Now..

  84. Six and one-half foot-pounds of work is required to compress a spring 4 inches from its natural length. Find the work required to compress the spring an additional one-half inch. (Round your answer to two decimal places.)

    This is what I did so far: 4 in =

  85. Consider the graph of y^2 = x(4-x)^2 (see link). Find the volumes of the solids that are generated when the loop of this graph is revolved about (a) the x-axis, (b) the y-axis, and (c) the line x = 4.

    goo.gl/photos/v5qJLDztqsZpHR9d7 I'm just having trouble

  86. ∫ (2x-1)^2 dx could have two answers:

    a) ((2x-1)^3)/6 + C b) 4/3x^3 - 2x^2 + x + C Now the question is, how are the two answers related? I attempted to answer the question by: "The two answers are related because when finding the derivative of those two

  87. I am given two integrals a and b

    a) ∫ 1/(1 + x^4) dx b) ∫ x/(1 + x^4) dx The main difference between the two integrals appears to be the "1" and "x" on the numerators. While they both resembles closely to the basic integration of arctan: ∫ du/(a^2 +

  88. Find the indefinite integral in two ways.

    ∫(2x-1)^2 dx The first way I used was using the power rule and chain rule with substitution. Let u = 2x - 1 du = 2 dx (1/2)∫ u^2 du (Applying power rule) (1/2) * (u^3/3) + C =(2x-1)^3/6 + C What would be another

  89. how much energy is released during the reaction of 2.5l diboron hexahydride with 5.65l chlorine gas?

  90. The area A between the graph of the function:

    g(t) = 4 - (4/t^2) and the t-axis over the interval [1, x] is: A(x) = ∫[1, x] (4 - (4/t^2)) dt a) Find the horizontal asymptote of the graph g. I believe the horizontal asymptote of graph g is g(t) = 4. b)

  91. Sketch the region given by the definite integral. Use geometric shapes and formulas to evaluate the integral (a > 0, r > 0).

    r ∫ sqrt(r^2 - x^2) dx -r While I recognize that this looks similar to a circle function, I'm not sure how to graph and evaluate

  92. Evaluate the integral using the following values.

    8 ∫ x^3 dx = 1020 2 8 ∫ x dx = 30 2 8 ∫ dx = 6 2 2 ∫ x^3 dx = ? 2

  93. Here is the link to the graph of f' in question:

    bit.ly/2oml70V I have a hard time trying to answer these kinds of questions when we're only given a graph of f'. a) Approximate the slope of f at x = 4. Explain. I believe the slope of f in this case would be

  94. In order to predict y-values using the equation of a regression line, what must be true about the correlation coefficient of the variables?

    A. The correlation between variables must be an x-value of a point on the graph. B. The correlation between variables

  95. At what point does the terminal side of the angle (5\pi )/(6) in standard position intersect the unit circle?

  96. The population of bacteria in a petri dish doubles every 12 h. The population of the bacteria is initially 500 organisms.

    How long will it take for the population of the bacteria to reach 800? Round your answer to the nearest tenth of an hour.

  97. How would I identify a set of coordinates (x, y, z) to be in which octant in a 3d space? Is it just based on the x-value? Depending on the x-value (1-8) used?

  98. When constructing a graph showing the population of two​ countries, an illustrator draws two different people with heights proportional to the populations. Identify a way in which the graph might be misleading. What is the general name for such graphs

  99. Just giving this a shot,

    Which of the following statements about RAM are TRUE? Select all that apply. a) Any part of RAM can be accessed at any time. b) RAM is an area of a computer that holds programs and data that are waiting to be processed, to be stored

  100. If the average atomic mass of Br is 79.90 amu, what is the percent abundance of each of its isotopes?

    How would we figure out the isotopes first before we calculate the percent abundance??


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