EP MATHEMATICAL EXCURSIONS-WEBASSIGN
4th Edition
ISBN: 9780357113028
Author: Aufmann
Publisher: CENGAGE CO
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 8, Problem 4RE
Evaluate each expression, where
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Determine whether each function is an injection and determine whether each is a surjection.
Let A
=
{a, b, c, d}, B = {a,b,c}, and C = {s, t, u,v}. Draw an arrow diagram of a function
for each of the following descriptions. If no such function exists, briefly explain why.
(a) A function f : AC whose range is the set C.
(b) A function g: BC whose range is the set C.
(c) A function g: BC that is injective.
(d) A function j : A → C that is not bijective.
Let f:R->R be defined by f(x)=x^(3)+5.(a) Determine if f is injective. why?(b) Determine if f is surjective. why?(c) Based upon (a) and (b), is f bijective? why?
Chapter 8 Solutions
EP MATHEMATICAL EXCURSIONS-WEBASSIGN
Ch. 8.1 - Determine the day of the week on which you were...Ch. 8.1 - Determine the day of the week on which Abraham...Ch. 8.1 - Determine the day of the week on which January 1,...Ch. 8.1 - Determine the day of the week on which Valentines...Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Prob. 4ESCh. 8.1 - Prob. 5ESCh. 8.1 - Prob. 6ES
Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Prob. 8ESCh. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Prob. 10ESCh. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Prob. 14ESCh. 8.1 - Evaluate each expression, where and indicate...Ch. 8.1 - Prob. 16ESCh. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Prob. 22ESCh. 8.1 - Prob. 23ESCh. 8.1 - Military Time. Evaluate each expression, where +...Ch. 8.1 - Evaluate each expression, where + and indicate...Ch. 8.1 - Prob. 26ESCh. 8.1 - Evaluate each expression, where + and indicate...Ch. 8.1 - Prob. 28ESCh. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Prob. 32ESCh. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Determine whether the congruence is true or false....Ch. 8.1 - Prob. 38ESCh. 8.1 - List five different natural numbers that are...Ch. 8.1 - List five different natural numbers that are...Ch. 8.1 - Perform the modular arithmetic. (9+15)mod7Ch. 8.1 - Prob. 42ESCh. 8.1 - Perform the modular arithmetic. (5+22)mod8Ch. 8.1 - Prob. 44ESCh. 8.1 - Perform the modular arithmetic. (42+35)mod3Ch. 8.1 - Prob. 46ESCh. 8.1 - Perform the modular arithmetic. (37+45)mod12Ch. 8.1 - Prob. 48ESCh. 8.1 - Prob. 49ESCh. 8.1 - Perform the modular arithmetic. (2510)mod4Ch. 8.1 - Prob. 51ESCh. 8.1 - Prob. 52ESCh. 8.1 - Prob. 53ESCh. 8.1 - Prob. 54ESCh. 8.1 - Perform the modular arithmetic. (1532)mod7Ch. 8.1 - Prob. 56ESCh. 8.1 - Perform the modular arithmetic. (68)mod9Ch. 8.1 - Prob. 58ESCh. 8.1 - Prob. 59ESCh. 8.1 - Prob. 60ESCh. 8.1 - Perform the modular arithmetic. (1418)mod5Ch. 8.1 - Prob. 62ESCh. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Prob. 66ESCh. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Clocks and Calendars. Use modular arithmetic to...Ch. 8.1 - Prob. 71ESCh. 8.1 - Prob. 72ESCh. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Prob. 75ESCh. 8.1 - Prob. 76ESCh. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Prob. 79ESCh. 8.1 - Prob. 80ESCh. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Find all whole number solutions of the congruence...Ch. 8.1 - Prob. 83ESCh. 8.1 - Find the additive inverse and the multiplicative...Ch. 8.1 - Find the additive inverse and the multiplicative...Ch. 8.1 - Prob. 86ESCh. 8.1 - Find the additive inverse and the multiplicative...Ch. 8.1 - Find the additive inverse and the multiplicative...Ch. 8.1 - Modular division can be performed by considering...Ch. 8.1 - Prob. 90ESCh. 8.1 - Prob. 91ESCh. 8.1 - Prob. 92ESCh. 8.1 - Prob. 93ESCh. 8.1 - Modular division can be performed by considering...Ch. 8.1 - Prob. 95ESCh. 8.1 - Prob. 96ESCh. 8.1 - Prob. 97ESCh. 8.1 - Prob. 98ESCh. 8.1 - Prob. 99ESCh. 8.1 - Many people consider the 13th of the month an...Ch. 8.2 - What is the ciphertext for the word CODE?Ch. 8.2 - Prob. 2EECh. 8.2 - Prob. 3EECh. 8.2 - Prob. 4EECh. 8.2 - Prob. 5EECh. 8.2 - ISBN Numbers. Determine whether the given number...Ch. 8.2 - ISBN Numbers. Determine whether the given number...Ch. 8.2 - Prob. 3ESCh. 8.2 - Prob. 4ESCh. 8.2 - Prob. 5ESCh. 8.2 - ISBN Numbers. Determine whether the given number...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - Prob. 10ESCh. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - ISBN Numbers. Determine the correct check digit...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - UPC Codes. Determine the correct check digit for...Ch. 8.2 - Prob. 23ESCh. 8.2 - Prob. 24ESCh. 8.2 - Money Orders Some money orders have serial numbers...Ch. 8.2 - Money Orders Some money orders have serial numbers...Ch. 8.2 - Air Travel Many printed airline tickets contain a...Ch. 8.2 - Air Travel Many printed airline tickets contain a...Ch. 8.2 - Air Travel Many printed airline tickets contain a...Ch. 8.2 - Prob. 30ESCh. 8.2 - Credit Card Numbers. Determine whether the given...Ch. 8.2 - Credit Card Numbers. Determine whether the given...Ch. 8.2 - Prob. 33ESCh. 8.2 - Credit Card Numbers. Determine whether the given...Ch. 8.2 - Prob. 35ESCh. 8.2 - Credit Card Numbers. Determine whether the given...Ch. 8.2 - Credit Card Numbers. Determine whether the given...Ch. 8.2 - Prob. 38ESCh. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Encryption. Encode the message by using a cyclical...Ch. 8.2 - Decoding. Use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding. Use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding. Use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding. Use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding, use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding, use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding, use a cyclical alphabetic encrypting...Ch. 8.2 - Decoding, use a cyclical alphabetic encrypting...Ch. 8.2 - Encryption Julius Caesar supposedly used an...Ch. 8.2 - Decoding Julius Caesar supposedly used an...Ch. 8.2 - Encryption Use the encrypting congruence...Ch. 8.2 - Encryption Use the encrypting congruence...Ch. 8.2 - Encryption Use the encrypting congruence...Ch. 8.2 - Encryption Use the encrypting congruence...Ch. 8.2 - Decoding Decode the message LOFT JGMK LBS MNWMK...Ch. 8.2 - Decoding Decode the message BTYW SCRBKN UCYN that...Ch. 8.2 - Prob. 61ESCh. 8.2 - Decoding Decode the message GBBZ OJQBWJ TBR GJHI...Ch. 8.2 - Money Orders Explain why the method used to...Ch. 8.2 - Prob. 64ESCh. 8.2 - Banking. When banks process an electronic funds...Ch. 8.3 - Prob. 1EECh. 8.3 - Prob. 2EECh. 8.3 - Prob. 3EECh. 8.3 - Prob. 4EECh. 8.3 - Prob. 5EECh. 8.3 - Prob. 1ESCh. 8.3 - Prob. 2ESCh. 8.3 - Prob. 3ESCh. 8.3 - Prob. 4ESCh. 8.3 - Prob. 5ESCh. 8.3 - Prob. 6ESCh. 8.3 - Prob. 7ESCh. 8.3 - Prob. 8ESCh. 8.3 - Prob. 9ESCh. 8.3 - Prob. 10ESCh. 8.3 - Prob. 11ESCh. 8.3 - Prob. 12ESCh. 8.3 - Prob. 13ESCh. 8.3 - Prob. 14ESCh. 8.3 - Prob. 15ESCh. 8.3 - Prob. 16ESCh. 8.3 - Prob. 17ESCh. 8.3 - Prob. 18ESCh. 8.3 - Prob. 19ESCh. 8.3 - Prob. 20ESCh. 8.3 - Prob. 21ESCh. 8.3 - Prob. 22ESCh. 8.3 - Prob. 23ESCh. 8.3 - Prob. 24ESCh. 8.3 - Prob. 25ESCh. 8.3 - Prob. 26ESCh. 8.3 - Prob. 27ESCh. 8.3 - Prob. 28ESCh. 8.3 - Prob. 29ESCh. 8.3 - Prob. 30ESCh. 8.3 - Prob. 31ESCh. 8.3 - Prob. 32ESCh. 8.3 - Prob. 33ESCh. 8.3 - Prob. 34ESCh. 8.3 - Refer to the group of permutations of the numbers...Ch. 8.3 - Prob. 36ESCh. 8.3 - Prob. 37ESCh. 8.3 - Prob. 38ESCh. 8.3 - Prob. 39ESCh. 8.3 - Prob. 40ESCh. 8.3 - Prob. 41ESCh. 8.3 - Prob. 42ESCh. 8.3 - Prob. 43ESCh. 8.3 - Prob. 44ESCh. 8.3 - Prob. 45ESCh. 8.3 - Prob. 46ESCh. 8.3 - Prob. 47ESCh. 8.3 - Prob. 48ESCh. 8.3 - Prob. 49ESCh. 8.3 - Prob. 50ESCh. 8.3 - Prob. 51ESCh. 8.3 - Prob. 52ESCh. 8.3 - Prob. 53ESCh. 8.3 - Prob. 54ESCh. 8.3 - Prob. 55ESCh. 8.3 - Consider the set of elements a,b,c,d with the...Ch. 8.3 - Prob. 57ESCh. 8.3 - Prob. 58ESCh. 8.3 - Prob. 59ESCh. 8.3 - Prob. 60ESCh. 8.3 - Prob. 61ESCh. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression, where and indicate...Ch. 8 - Evaluate each expression. Where + and indicate...Ch. 8 - Evaluate each expression. Where + and indicate...Ch. 8 - Prob. 11RECh. 8 - Prob. 12RECh. 8 - Prob. 13RECh. 8 - Prob. 14RECh. 8 - Prob. 15RECh. 8 - Prob. 16RECh. 8 - Prob. 17RECh. 8 - Prob. 18RECh. 8 - Prob. 19RECh. 8 - Prob. 20RECh. 8 - Prob. 21RECh. 8 - Prob. 22RECh. 8 - Clocks and Calendars. Use modular arithmetic to...Ch. 8 - Prob. 24RECh. 8 - Prob. 25RECh. 8 - Find all whole number solutions of the congruence...Ch. 8 - Prob. 27RECh. 8 - Prob. 28RECh. 8 - Prob. 29RECh. 8 - Prob. 30RECh. 8 - Prob. 31RECh. 8 - Prob. 32RECh. 8 - ISBN Numbers. Determine the correct check digit...Ch. 8 - ISBN Numbers. Determine the correct check digit...Ch. 8 - UPC Codes. Determine the correct check digit for...Ch. 8 - Prob. 36RECh. 8 - Prob. 37RECh. 8 - Prob. 38RECh. 8 - Prob. 39RECh. 8 - Prob. 40RECh. 8 - Encryption. Encode the message using a cyclical...Ch. 8 - Encryption. Encode the message using a cyclical...Ch. 8 - Encryption. Use a cyclical alphabetic encrypting...Ch. 8 - Prob. 44RECh. 8 - Encryption Use the encrypting congruence...Ch. 8 - Encryption Decode the message WEU LKGGMF NHM NMGN,...Ch. 8 - Prob. 47RECh. 8 - Prob. 48RECh. 8 - Prob. 49RECh. 8 - Prob. 50RECh. 8 - Prob. 51RECh. 8 - Prob. 52RECh. 8 - Prob. 53RECh. 8 - Use symbolic notation, shown below, for the...Ch. 8 - Prob. 55RECh. 8 - Prob. 56RECh. 8 - Prob. 57RECh. 8 - Prob. 58RECh. 8 - Evaluate each expression, where and indicate...Ch. 8 - January 1, 2017, was a Sunday. What day of the...Ch. 8 - Determine whether the congruence is true or false....Ch. 8 - Prob. 4TCh. 8 - Prob. 5TCh. 8 - Prob. 6TCh. 8 - Scheduling Disregarding A.M. or P.M., if it is now...Ch. 8 - Prob. 8TCh. 8 - Prob. 9TCh. 8 - Find the additive inverse and the multiplicative...Ch. 8 - ISBN Number Determine the correct check digit for...Ch. 8 - UPC Codes Determine the correct check digit for...Ch. 8 - Prob. 13TCh. 8 - Encryption Encrypt the plaintext message REPORT...Ch. 8 - Prob. 15TCh. 8 - Prob. 16TCh. 8 - Prob. 17TCh. 8 - Prob. 18TCh. 8 - In the permutation group of the numbers 1 2 3,...Ch. 8 - Prob. 20T
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, subject and related others by exploring similar questions and additional content below.Similar questions
- 25-30. Normal and tangential components For the vector field F and curve C, complete the following: a. Determine the points (if any) along the curve C at which the vector field F is tangent to C. b. Determine the points (if any) along the curve C at which the vector field F is normal to C. c. Sketch C and a few representative vectors of F on C. 25. F = (2½³, 0); c = {(x, y); y − x² = 1} 26. F = x (23 - 212) ; C = {(x, y); y = x² = 1}) , 2 27. F(x, y); C = {(x, y): x² + y² = 4} 28. F = (y, x); C = {(x, y): x² + y² = 1} 29. F = (x, y); C = 30. F = (y, x); C = {(x, y): x = 1} {(x, y): x² + y² = 1}arrow_forward٣/١ B msl kd 180 Ka, Sin (1) I sin () sin(30) Sin (30) اذا ميريد شرح الكتب بس 0 بالفراغ 3) Cos (30) 0.866 4) Rotating 5) Synchronous speed, 120 x 50 G 5005 1000 s = 1000-950 Copper bosses 5kW Rotor input 5 0.05 : loo kw 6) 1 /0001 ined sove in peaper I need a detailed solution on paper please وه اذا ميريد شرح الكتب فقط ١٥٠ DC 7) rotor a ' (y+xlny + xe*)dx + (xsiny + xlnx + dy = 0. Q1// Find the solution of: ( 357arrow_forward۳/۱ R₂ = X2 2) slots per pole per phase 3/31 B. 180 msl Kas Sin (I) 1sin() sin(30) Sin (30) اذا ميريد شرح الكتب بس 0 بالفراغ 3) Cos (30): 0.866 4) Rotating 5) Synchronous speeds 120×50 looo G 1000-950 1000 Copper losses 5kw Rotor input 5 loo kw 0.05 6) 1 اذا ميريد شرح الكتب فقط look 7) rotor DC ined sove in peaper I need a detailed solution on paper please 0 64 Find the general solution of the following equations: QI//y(4)-16y= 0. Find the general solution of the following equations: Q2ll yll-4y/ +13y=esinx.arrow_forward
- R₂ = X2 2) slots per pole per phase = 3/31 B-180 60 msl kd Kas Sin () 2 I sin (6) sin(30) Sin (30) اذا مريد شرح الكتب بس 0 بالفراغ 3 Cos (30) 0.866 4) Rotating ined sove in peaper 5) Synchronous speed s 120×50 6 s = 1000-950 1000 Copper losses 5kw Rotor input 5 0.05 6) 1 loo kw اذا ميريد شرح الكتب فقط Look 7) rotov DC I need a detailed solution on paper please 0 64 Solve the following equations: 0 Q1// Find the solution of: ( y • with y(0) = 1. dx x²+y²arrow_forwardR₂ = X2 2) slots per pole per phase = 3/3 1 B-180-60 msl Ka Sin (1) Isin () sin(30) Sin (30) اذا ميريد شرح الكتب بس 0 بالفراغ 3) Cos (30) 0.866 4) Rotating 5) Synchronous speed, 120 x 50 s = 1000-950 1000 Copper losses 5kw Rotor input 5 6) 1 0.05 G 50105 loo kw اذا ميريد شرح الكتب فقط look 7) rotov DC ined sove in peaper I need a detailed solution on paper please 064 2- A hot ball (D=15 cm ) is cooled by forced air T.-30°C, the rate of heat transfer from the ball is 460.86 W. Take for the air -0.025 Wim °C and Nu=144.89, find the ball surface temperature a) 300 °C 16 b) 327 °C c) 376 °C d) None か = 750 01arrow_forwardAnswer questions 8.3.3 and 8.3.4 respectively 8.3.4 .WP An article in Medicine and Science in Sports and Exercise [“Electrostimulation Training Effects on the Physical Performance of Ice Hockey Players” (2005, Vol. 37, pp. 455–460)] considered the use of electromyostimulation (EMS) as a method to train healthy skeletal muscle. EMS sessions consisted of 30 contractions (4-second duration, 85 Hz) and were carried out three times per week for 3 weeks on 17 ice hockey players. The 10-meter skating performance test showed a standard deviation of 0.09 seconds. Construct a 95% confidence interval of the standard deviation of the skating performance test.arrow_forward
- 8.6.7 Consider the tire-testing data in Exercise 8.2.3. Compute a 95% tolerance interval on the life of the tires that has confidence level 95%. Compare the length of the tolerance interval with the length of the 95% CI on the population mean. Which interval is shorter? Discuss the difference in interpretation of these two intervals.arrow_forward8.6.2 Consider the natural frequency of beams described in Exercise 8.2.8. Compute a 90% prediction interval on the diameter of the natural frequency of the next beam of this type that will be tested. Compare the length of the prediction interval with the length of the 90% CI on the population mean. 8.6.3 Consider the television tube brightness test described in Exercise 8.2.7. Compute a 99% prediction interval on the brightness of the next tube tested. Compare the length of the prediction interval with the length of the 99% CI on the population mean.arrow_forwardAnswer question S8 stepwisearrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Algebra: Structure And Method, Book 1AlgebraISBN:9780395977224Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. ColePublisher:McDougal Littell
College Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill
Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL
Mathematics For Machine TechnologyAdvanced MathISBN:9781337798310Author:Peterson, John.Publisher:Cengage Learning,
Trigonometry (MindTap Course List)TrigonometryISBN:9781305652224Author:Charles P. McKeague, Mark D. TurnerPublisher:Cengage Learning
Algebra: Structure And Method, Book 1
Algebra
ISBN:9780395977224
Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. Cole
Publisher:McDougal Littell
College Algebra (MindTap Course List)
Algebra
ISBN:9781305652231
Author:R. David Gustafson, Jeff Hughes
Publisher:Cengage Learning
Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
Mathematics For Machine Technology
Advanced Math
ISBN:9781337798310
Author:Peterson, John.
Publisher:Cengage Learning,
Trigonometry (MindTap Course List)
Trigonometry
ISBN:9781305652224
Author:Charles P. McKeague, Mark D. Turner
Publisher:Cengage Learning
Finite State Machine (Finite Automata); Author: Neso Academy;https://www.youtube.com/watch?v=Qa6csfkK7_I;License: Standard YouTube License, CC-BY
Finite State Machine (Prerequisites); Author: Neso Academy;https://www.youtube.com/watch?v=TpIBUeyOuv8;License: Standard YouTube License, CC-BY