Francesca

Most popular questions and responses by Francesca
  1. Thermal Physics

    Two cars collide head on while each is travelling at 80 km/hr. Suppose all of their kinetic energy is transformed into thermal energy. What is the temperature increase of each car? [You may assume that the specific heat capacity of each car is that of

    asked on May 20, 2011
  2. chemistry

    Calculate the pH for each of the following cases in the titration of 50.0 mL of 0.150 M HClO(aq) with 0.150 M KOH(aq). The ionization constant for HClO is 4.0x10^-8. pH before the addition of any KOH? pH after the addition of 25 mL of KOH? Please show the

    asked on March 10, 2015
  3. Discrete Math

    A factory makes automobile parts. Each part has a code consisting of a letter and three digits, such as C117, O076, or Z920. Last week the factory made 60,000 parts. Prove that there are at least three parts that have the same serial number.

    asked on April 20, 2011
  4. CHemistry

    Calculate the pH at the equivalence point for the titration of 0.140 M methylamine (CH3NH2) with 0.140 M HCl. The Kb of methylamine is 5.0× 10–4.

    asked on March 10, 2015
  5. Science

    Please suppose that the actual temperature is above 32 degrees F but the wind chill or real feel temperature is below 32 degrees F. Could water still freeze on the roadway surfaces?

    asked on March 8, 2019
  6. Math

    1.) Find the producers' surplus if the supply function is: S(q) = q^7/2+3q^5/2 + 54. Assume the supply and demand are in equilibrium at q= 25. 2.) S(q) = q^2 + 12q and D(q) = 900 - 18q - q^2 The point at which the supply and demand are equilibrium is (15,

    asked on June 14, 2012
  7. Computing in Security (Conversion Help)

    1.) Express each decimal number as an 8-bit binary number in the 2's complement form and then find the negative of the representation of that number in two’s compliment a.) +18 b) -117 Thanks for any help!

    asked on September 8, 2011
  8. Discrete Math

    Theorem: For every integer n, if x and y are positive integers with max(x, y) = n, then x = y. Basic Step: Suppose that n = 1. If max(x, y) = 1 and x and y are positive integers, we have x = 1 and y = 1. Inductive Step: Let k be a positive integer. Assume

    asked on March 25, 2011
  9. Physics

    An archer shoots an arrow horizontally at a target 14 m away. The arrow is aimed directly at the center of the target, but it hits 59 cm lower. What was the initial speed of the arrow? So, I am trying to find find v₀x. . .

    asked on February 16, 2011
  10. Math

    1.) Find the producers' surplus if the supply function is: S(q) = q^7/2+3q^5/2 + 54. Assume the supply and demand are in equilibrium at q= 25. 2.) S(q) = q^2 + 12q and D(q) = 900 - 18q - q^2 The point at which the supply and demand are equilibrium is (15,

    asked on June 15, 2012
  11. Discrete Math

    Is this correct? • Using the Principle of Inclusion-Exclusion, find the number of integers between 1 and 2000 (inclusive) that are divisible by at least one of 2, 3, 5, 7. A = {n| 1 ≤ n ≤ 2000, 2 |n} B = {n| 1 ≤ n ≤ 2000, 3 |n} C = {n| 1 ≤ n

    asked on April 12, 2011
  12. chemistry

    Data given are related to the Born-Haber cycle for HCl Calculate the amount of energy lost when the ionic species return to their molecular form. Atomization of ½H2(g)=217.6KJ/mol 1st Ionisation of ½H2(g)=1312KJ/mol Atomization of ½Cl2(g)=121 KJ/mol 1st

    asked on March 28, 2012
  13. Discrete Math

    Find f(1), f(2), and f(3) if f(n) is defined recursively by f(0) = 1 and for n = 0, 1, 2, . . . • f(n+1) = f(n) + 2 So, would it be f(n) = f(n+1) + 2? Or would I just keep it like the original and plug in 1, 2, 3. Thanks for any helpful replies.

    asked on March 26, 2011
  14. Discrete Math

    An arithmetic sequence begins, 116, 109, 102 Find the 300th term of this sequence.

    asked on March 28, 2011
  15. Discrete Math

    Solve the recurrence relation a_n = -6a_n - 1 + 7a_n-2, n ≥ 2, given a₀ = 32, a₁ = -17. This is what I have figured out so far: polynomial: x² + 6x - 7 distinct roots: 1 and -7 I do not understand how to find C₁ and C₂. How do I complete this

    asked on April 5, 2011
  16. Discrete Math

    Congruence True or False: (give reason) _ __ 2 ∈ 18 (mod 8) Can someone please help with this problem? I'm confused. . . Thanks for any helpful replies.

    asked on March 14, 2011
  17. Finance

    An income-producing property is priced at $600,000 and is expected to generatethe following after-tax cash flows: Year 1: $42,000; Year 2: $44,000; Year 3:$45,000; Year 4: $50,000; and Year 5: $650,000. Would an investor with arequired after-tax rate of

    asked on December 6, 2012
  18. Math

    Can someone please help me find the derivative of the following: y = (-9e^7x) / (5x+3) Thank you!

    asked on June 3, 2012
  19. Discrete Math

    Use mathematical induction to establish the following formula. n Σ i² / [(2i-1)(2i+1)] = n(n+1) / 2(2n+1) i=1 Thanks for any helpful replies :)

    asked on March 22, 2011
  20. Social Studies

    The effectiveness of Roman rule can easily be seen in the fact that the fall of Rome led to 1) political chaos and economic collapse in western Europe 2) the rapid rise of a new European empire

    asked on January 10, 2009
  21. Accounting

    Sierra Company is considering a long-term investment project called ZIP. ZIP will require an investment of $121,200. It will have a useful life of 4 years and no salvage value. Annual revenues would increase by $79,180, and annual expenses (excluding

    asked on July 15, 2012
  22. IP address assignment

    Imagine that you are a system administrator for a company, and that the company operates from two locations Phoenix and Boston. Phoenix has 350 hosts and Boston has 2100. Given that the following class C IP addresses have been assigned to your company as a

    asked on September 14, 2011
  23. Chemistry

    Calculate the morality of a solution that contains a 4.0 mol of a solute dissolved in 12.0L of solution

    asked on March 4, 2013
  24. CIS

    1.) Encrypt the hexadecimal message F9E8 using the Rail Fence cipher for binary numbers with 3 Rails. [Give answer in hexadecimal encrypted message] 2.) Decrypt the hexadecimal encrypted message CDEF created by the Rail Fence cipher for binary numbers with

    asked on September 15, 2011
  25. Discrete Math

    Use mathematical induction to prove the truth of each of the following assertions for all n ≥1. n³ + 5n is divisible by 6 I really do not understand this to much. This is what I have so far: n = 1, 1³ - 5(1) = 6, which is divisible by 6 Then I really

    asked on March 21, 2011
  26. Discrete Math

    So, I uploaded the figure in photobucket, and if you type flutegirl516 in the search bar you will see it's the first photo. F:B→C, h:C→B, and G:A→C Is F°h°G defined? If so, what is its domain and range? Yes it is defined. And I thought that the

    asked on February 19, 2011
  27. Discrete Math

    f: A→B, g :B→A Is g ° f defined? If so, what is its domain and range? Any suggestions?

    asked on February 17, 2011
  28. Discrete Math

    I want to verify that this is correct: An arithmetic sequence begins, 116, 109, 102 • Determine whether -480 belongs to this sequence, if it does, what is its term number? -480 = 116 + (n - 1)(-7) n - 1 = 85.142. . . So, that means -480 does not belong

    asked on March 29, 2011
  29. Science

    What is water treatment? Is it also the same with water filtration? Please answer! Thanks

    asked on November 3, 2017
  30. Business Finance

    Neville Corporation, an amusement park, is considering a capital investment in a new exhibit. The exhibit would cost $174,777 and have an estimated useful life of 9 years. It will be sold for $69,200 at that time. (Amusement parks need to rotate exhibits

    asked on July 3, 2012
  31. Discrete Math

    Use mathematical induction to prove the truth of each of the following assertions for all n ≥1. 5^2n – 2^5n is divisible by 7 If n = 1, then 5^2(1) - 2^5(1) = -7, which is divisible by 7. For the inductive case, assume k ≥ 1, and the result is true

    asked on March 23, 2011
  32. Discrete Math

    Hi, I need help with interpreting a figure. You can find it one photobucket. First, type in flutegirl516 in the search bar and then click on the message that says: "Are you looking for the Photobucket user flutegirl516? Click here to see this user's

    asked on February 22, 2011
  33. Discrete Math

    Find g ° f f(x) = {(1, 2), (2,1), (3,1), (4, 4)} g(x) = {(1, 2), (2,4), (3, 1), (4, 3)}

    asked on February 15, 2011
  34. social studies

    what are the best desciiptions of both push and pull facors?

    asked on January 19, 2010
  35. Math

    Use the definite integral to find the area between the x-axis over the indicated interval. f(x) = 36 - x^2; [-1,13] So, what does be the area between the x-axis and f(x) equal? Thank you for any help! I'm really confused with this problem!

    asked on June 14, 2012
  36. Math

    How do I solve for negative modular arithmetic? Here is an example: -45 mod 13 = 7, but how?

    asked on October 10, 2011
  37. Computing in Security (Conversion Help)

    1.) Encrypt the hexadecimal message F9E8 using the Rail Fence cipher for binary numbers with 3 Rails. [Give answer in hexadecimal encrypted message] 2.) Decrypt the hexadecimal encrypted message CDEF created by the Rail Fence cipher for binary numbers with

    asked on September 18, 2011
  38. Physics of materials

    Gaseous nitrogen has a density of 1.17 kg/m3 and liquid nitrogen has a density of 810 kg/m3. [The relative molecular mass of nitrogen is 28.0] What is the mean volume per nitrogen molecule in each case? What is the mean separation between nitrogen

    asked on May 18, 2011
  39. Discrete Math

    isisDOTpolyDOTedu/courses/discretemath/problemsDOTpdf Link is above can you please take a look? Specifically #21 on pg. 345. [There are 900 3DN], I need help with g-h. Thank you.

    asked on April 19, 2011
  40. Discrete Math

    Can someone help? Very confused. . . John Sununus was once the governor of New Hampshire, and his name reminds one of the authors of a palindrome (a words which is spelt the same way forwards as backwards, such as SUNUNUS). How many seven-letter

    asked on April 12, 2011
  41. Discrete Math

    Solve the recurrence relation a_n = -2a_n-1 + 15a_n-2, n ≥ 2, given a₀ = 1, a₁ = -1. x² + 2x - 15, the distinct roots 3 and -5, so a_n = C₁(3^n) + C₂(-5)^n. The initial condition gives a₀ = 1 = C₁ - C₂, a₁ = -1 = 3C₁ - 5C₂. We obtain

    asked on April 5, 2011
  42. Discrete Math

    Determine the domain and range of: y = 5 – [1/ (1 + x)] So, would the domain be all real numbers except -1? And would the range be all real numbers except zero? I'm really confused. . .

    asked on February 15, 2011
  43. Geometery

    I need to know the laws of triangle inequality. i need help what is triangle in equality?

    asked on January 6, 2010
  44. maths

    on an island without squirrels some squirrels are introduced. a mathematical model of the population growth of squirrels on the island is given by the function f defined by f(x)= 1320/(1 + e^(5,1-0.66x)) where x is the time in years after the introduction

    asked on November 8, 2017
  45. Physics

    A baseball is hit off the edge of a cliff horizontally at a speed of 30 m/s. It takes the ball 3 seconds to reach the ground, with no air resistance. How high is the cliff wall?

    asked on October 12, 2015
  46. Math

    what is 18 percent of 240?

    asked on October 2, 2012
  47. Math

    how do you solve: 4=1(2)/(x-2) Thank you!

    asked on June 17, 2012
  48. Math

    Solve for x. .006x^3=8889 x = approx 114, but I don't understand how to get that answer. Can anyone help me solve? Thank you!

    asked on June 7, 2012
  49. Accounting

    The balance sheet of Burger King reports current assets of $30,500 and current liabilities of $15,800. Calculate the current ratio of Burger King and detemine whether it will increase or decrease as a result of the following transactions: -Paid $2,030 cash

    asked on January 13, 2012
  50. Math

    Find the value of x: 20x ≡ 9 (mod 15)

    asked on October 11, 2011
  51. Math

    How do I solve for negative modular arithmetic? Here is an example: -45 mod 13 = 7, but how?

    asked on October 10, 2011
  52. Discrete Math

    Why use mathematical induction to get the sum of a sequence? Also, if there are any websites you can recommend that will be a help too. However, I need an explanation rather than examples. Thank you for any helpful replies.

    asked on April 2, 2011
  53. Math

    Let f(x^2/3). Find f(S) if S = {1,5,7,11}.

    asked on February 24, 2011
  54. Discrete Math

    Find the inverse of f: R→R given by f(x) = x³ – 2

    asked on February 15, 2011
  55. Math

    Can someone please calculate this: 48(-1/2)^6 The answer is 3/2, but I get 3/4. What am I dong wrong?

    asked on March 29, 2011
  1. Math

    She’s correct

    posted on April 11, 2018
  2. Science

    Thank you!

    posted on November 3, 2017
  3. math

    sign a pastition

    posted on September 13, 2016
  4. Physics

    The given are (a) the speed of sound, which is 395 m/s, (b) the velocity of the moving source, which is 12 m/s, and (c) the frequency of the sound both cars are emitting, which is 395 Hz. Let's assume that f{o} is the frequency the observer can hear and

    posted on October 19, 2015
  5. Ecology

    BYWEEE

    posted on March 17, 2015
  6. Finance

    Also, how would you calculate the IRR? Thank you for any help!

    posted on December 6, 2012
  7. Math

    it is a

    posted on October 2, 2012
  8. Math

    Thank you!

    posted on June 17, 2012
  9. Math

    1.) Find the producers' surplus if the supply function is: S(q) = q^7/2+3q^5/2 + 54. Assume the supply and demand are in equilibrium at q= 25. 2.) S(q) = q^2 + 12q and D(q) = 900 - 18q - q^2 The point at which the supply and demand are equilibrium is (15,

    posted on June 15, 2012
  10. Math

    588 is the correct answer!**

    posted on June 14, 2012
  11. Math

    588 is the correct answer? But, I don't understand how to get to that number. How did you calculate that? Sorry, that may be a lot to type out

    posted on June 14, 2012
  12. Math

    Thank you!

    posted on June 7, 2012
  13. Math

    Thank you guys!

    posted on June 3, 2012
  14. Accounting

    Any help?

    posted on January 15, 2012
  15. Math

    Thanks for your help! Also, I am kind of confused about finding the value of x. Example: 9x ≡ 1 mod 10 How do I solve this?

    posted on October 11, 2011
  16. CIS

    Sorry it's computing in security, so I guess that would fall under computers. . .

    posted on September 16, 2011
  17. IP address assignment

    Yea I tried doing a google search, but nothing good explaining where to start. Thnx for the reply though

    posted on September 14, 2011
  18. Discrete Math

    THANK YOU! :)

    posted on April 21, 2011
  19. Discrete Math

    Basically for the MPD problem I have to make it more precise.

    posted on April 13, 2011
  20. Discrete Math

    Ok now I am confused again with 5:08, it seems the same as the first subpart of the problem. They can't be the same answer, for this one: How many seven-letter palindromes contain at most three different letters one of which is S? And for the MPD problem

    posted on April 13, 2011
  21. Discrete Math

    Can you at all help with this? Multiple personality disorder (MPD) is a condition in which different personalities exist within one person and at various times control that person’s behavior. In a recent survey of people with MPD, it was reported that

    posted on April 13, 2011
  22. Discrete Math

    Oh ok so there are 13800 that contain at most three different letters one of which is S.

    posted on April 13, 2011
  23. Discrete Math

    So, how many seven-letter palindromes contain at most three different letters one of which is S? We would start out with 26^3, but I don't understand how to make sure S will be included as one of the different letters. Any suggestions? Thank you.

    posted on April 13, 2011
  24. Discrete Math

    Oh okay I think I am following. . .

    posted on April 13, 2011
  25. Discrete Math

    To be honest I haven't started yet, but your method sounds like a step in the right direction. . .I'll play around with it for a little and see what I get. . .If you figure out anything post. Hopefully someone who knows something will post cuz I'm lost

    posted on April 12, 2011
  26. Discrete Math

    Any suggestions?

    posted on April 12, 2011
  27. Discrete Math

    Okay I continued the first problem: |A ∩ B| = [2000/6] = 333 |B ∩ C| = [2000/15] = 133 |C ∩ D| = [2000/35] = 57 |A ∩ D| = [2000/14] = 142 |A ∩ B ∩ C ∩ D| = [2000/210] = 9 1000 + 666 + 400 + 285 - 333 - 133 - 57 - 142 + 9 = 1695

    posted on April 12, 2011
  28. Discrete Math

    Hey thanks a lot for help!

    posted on April 6, 2011
  29. Discrete Math

    Well a_1 = 37 not 31

    posted on April 6, 2011
  30. Discrete Math

    So, going back to the previous 9:05. The solution is a_n = 40(1)^n - 3(1)^n, is this correct or way off?

    posted on April 6, 2011
  31. Discrete Math

    How about this: Solve the recurrence relation a_n+1 = -8a_n – 16a_n - 1, n ≥ 1, given a₀ = 5, a₁ = 17. Characteristic polynomial is: x^2 + 8x + 16 with distinct roots -4. Since the roots are equal a0 = 5 = C1(-4)^0 + C2(0)(-4)^0 making C1 = 5,

    posted on April 6, 2011
  32. Discrete Math

    So the characteristic roots are 1?

    posted on April 6, 2011
  33. Discrete Math

    Idk what happened at 7:24 I think my computer had a glitch or something and it reposted. This one is throwing me for a loop: Solve the recurrence relation a_n = 2a_n - 1 – a_n -2, n ≥ 2, given a₀ = 40, a₁ = 37. Characteristic polynomial: x^2 - 2 +

    posted on April 6, 2011
  34. Discrete Math

    Oh I feel dumb. . . Ok so now a_n = C_1(1)^n + C_2(-6)^n a0 = C_1 + C_2 = 5 (1) a1 = C_1 - 6C_2 = 19 (2) So to find C1 I eliminated it by 6(1) + (2)

    posted on April 5, 2011
  35. Discrete Math

    Thank you so much for your help! I think I am getting the hang of it better. Can you please check: Solve the recurrence relation a_n = -5a_n - 1 + 6a_n - 2, n ≥ 2, given a₀ = 5, a₁ = 19. characteristic polynomial is x^2 + 5x - 6 it has the distinct

    posted on April 5, 2011
  36. Discrete Math

    Oops posted twice. . .Sorry

    posted on April 5, 2011
  37. Discrete Math

    If you don't mind can you help with this problem? Solve the recurrence relation an+1 = 7an – 10an - 1, n ≥ 2, given a₁ = 10, a₂ = 29. The characteristic polynomial is x^2 - 7 + 10 with characteristic roots 2 and 5. Once again I get confused when I

    posted on April 5, 2011
  38. Discrete Math

    Sorry I still don't get it. Can someone please explain?

    posted on April 5, 2011
  39. Discrete Math

    REVISED QUESTION: Why use mathematical induction to prove the sum of a sequence is valid?

    posted on April 2, 2011
  40. Math

    So, this is how far I got. . .I getting weird numbers. . . -3072(1 - (-1/2)⁹) ------------------- = 1 - (-1/2)

    posted on March 29, 2011
  41. Math

    Thank you for responding. Hmm... IDK. . .I'll have to ask if that's a typo on the other end. Hey do you mind seeing if this is correct, and helping with the second part? Consider the geometric sequence that begins -3072 and common ratio –1/2. Find the

    posted on March 29, 2011
  42. Discrete Math

    Thank you!

    posted on March 29, 2011
  43. Discrete Math

    OK thank you!

    posted on March 29, 2011
  44. Discrete Math

    Yes, they both follow the same recursive definition. I was just trying the second part on my own to see if I understand. Sorry about the misunderstanding. . .

    posted on March 26, 2011
  45. Discrete Math

    f(n) is defined recursively by f(0) = 1 and for n = 0, 1, 2, . . . Find f(1), f(2), f(3)

    posted on March 26, 2011