Finite Mathematics and Calculus with Applications
1st Edition
ISBN: 9781323188361
Author: Margaret Lial
Publisher: Pearson Education
expand_more
expand_more
format_list_bulleted
Videos
Question
Chapter 6, Problem 3RE
To determine
Whether the statement “A truth table can have an odd number of rows” is true or false.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Find integrating factor
Draw the vertical and horizontal asymptotes. Then plot the intercepts (if any), and plot at least one point on each side of each vertical asymptote.
Draw the asymptotes (if there are any). Then plot two points on each piece of the graph.
Chapter 6 Solutions
Finite Mathematics and Calculus with Applications
Ch. 6.1 - Is the following statement compound? I bought Ben...Ch. 6.1 - Write the negation of the following statement....Ch. 6.1 - Write the negation of the following inequality. 4x...Ch. 6.1 - Write the symbolic statement in words. h r.Ch. 6.1 - Let p represent 7 2 and q represent 4 3. Find...Ch. 6.1 - If p is false, q is true, and r is false, find the...Ch. 6.1 - Let p represent 7 2, q represent 4 3, and r...Ch. 6.1 - Decide whether each of the following is a...Ch. 6.1 - Decide whether each of the following is a...Ch. 6.1 - Prob. 3E
Ch. 6.1 - Prob. 4ECh. 6.1 - Prob. 5ECh. 6.1 - Prob. 6ECh. 6.1 - Prob. 7ECh. 6.1 - Prob. 8ECh. 6.1 - Prob. 9ECh. 6.1 - Prob. 10ECh. 6.1 - Prob. 11ECh. 6.1 - Prob. 12ECh. 6.1 - Prob. 13ECh. 6.1 - Prob. 14ECh. 6.1 - Prob. 15ECh. 6.1 - Prob. 16ECh. 6.1 - Prob. 17ECh. 6.1 - Prob. 18ECh. 6.1 - Try to negate the sentence The exact number of...Ch. 6.1 - Prob. 20ECh. 6.1 - Prob. 21ECh. 6.1 - Prob. 22ECh. 6.1 - Prob. 23ECh. 6.1 - Let b represent the statement Im getting better...Ch. 6.1 - Prob. 25ECh. 6.1 - Prob. 26ECh. 6.1 - Prob. 27ECh. 6.1 - Prob. 28ECh. 6.1 - Prob. 29ECh. 6.1 - Prob. 30ECh. 6.1 - Prob. 31ECh. 6.1 - Prob. 32ECh. 6.1 - Prob. 33ECh. 6.1 - Prob. 34ECh. 6.1 - Prob. 35ECh. 6.1 - Prob. 36ECh. 6.1 - Prob. 37ECh. 6.1 - Prob. 38ECh. 6.1 - Prob. 39ECh. 6.1 - Prob. 40ECh. 6.1 - Prob. 41ECh. 6.1 - Prob. 42ECh. 6.1 - Prob. 43ECh. 6.1 - Prob. 44ECh. 6.1 - Prob. 45ECh. 6.1 - Prob. 46ECh. 6.1 - Prob. 47ECh. 6.1 - Prob. 48ECh. 6.1 - Prob. 49ECh. 6.1 - Prob. 50ECh. 6.1 - Prob. 51ECh. 6.1 - Prob. 52ECh. 6.1 - Prob. 53ECh. 6.1 - Prob. 54ECh. 6.1 - Prob. 55ECh. 6.1 - Prob. 56ECh. 6.1 - Prob. 57ECh. 6.1 - Prob. 58ECh. 6.1 - Prob. 59ECh. 6.1 - Prob. 60ECh. 6.1 - Prob. 61ECh. 6.1 - Prob. 62ECh. 6.1 - Prob. 63ECh. 6.1 - Prob. 64ECh. 6.1 - Prob. 65ECh. 6.1 - Prob. 66ECh. 6.1 - Prob. 67ECh. 6.1 - Prob. 68ECh. 6.1 - Prob. 69ECh. 6.1 - Prob. 70ECh. 6.1 - Prob. 71ECh. 6.1 - Prob. 72ECh. 6.1 - Prob. 73ECh. 6.1 - Prob. 74ECh. 6.1 - Prob. 75ECh. 6.1 - Social Sciences Law The following excerpts appear...Ch. 6.1 - Social Sciences Law The following excerpts appear...Ch. 6.1 - Social Sciences Law The following excerpts appear...Ch. 6.1 - Prob. 81ECh. 6.1 - Prob. 82ECh. 6.1 - Prob. 83ECh. 6.1 - Prob. 84ECh. 6.1 - Prob. 85ECh. 6.1 - Prob. 86ECh. 6.1 - Prob. 87ECh. 6.1 - Prob. 88ECh. 6.2 - Construct a truth table for p (p q). If p and q...Ch. 6.2 - Prob. 2YTCh. 6.2 - Find the negation of the following statement: You...Ch. 6.2 - Prob. 1WECh. 6.2 - Prob. 2WECh. 6.2 - Prob. 1ECh. 6.2 - Prob. 2ECh. 6.2 - Prob. 3ECh. 6.2 - Prob. 4ECh. 6.2 - Prob. 5ECh. 6.2 - Prob. 6ECh. 6.2 - If the truth table for a certain compound...Ch. 6.2 - Is it possible for the truth table of a compound...Ch. 6.2 - Prob. 9ECh. 6.2 - Prob. 10ECh. 6.2 - Prob. 11ECh. 6.2 - Prob. 12ECh. 6.2 - Prob. 13ECh. 6.2 - Prob. 14ECh. 6.2 - Prob. 15ECh. 6.2 - Prob. 16ECh. 6.2 - Prob. 17ECh. 6.2 - Prob. 18ECh. 6.2 - Construct a truth table for each compound...Ch. 6.2 - Prob. 20ECh. 6.2 - Prob. 21ECh. 6.2 - Prob. 22ECh. 6.2 - Prob. 23ECh. 6.2 - Prob. 24ECh. 6.2 - Prob. 25ECh. 6.2 - Prob. 26ECh. 6.2 - Write the negation of each statement, applying De...Ch. 6.2 - Write the negation of each statement, applying De...Ch. 6.2 - Prob. 29ECh. 6.2 - Prob. 30ECh. 6.2 - Prob. 31ECh. 6.2 - Prob. 32ECh. 6.2 - Prob. 33ECh. 6.2 - Prob. 34ECh. 6.2 - Prob. 35ECh. 6.2 - Prob. 36ECh. 6.2 - Decide whether the following compound statements...Ch. 6.2 - Prob. 38ECh. 6.2 - Prob. 39ECh. 6.2 - Prob. 40ECh. 6.2 - Prob. 41ECh. 6.2 - Prob. 42ECh. 6.2 - Prob. 43ECh. 6.2 - Prob. 44ECh. 6.2 - Guarantees The guarantee on a brand of vacuum...Ch. 6.2 - Prob. 46ECh. 6.2 - Prob. 47ECh. 6.2 - Law The following statement appears in a guide to...Ch. 6.2 - Prob. 49ECh. 6.2 - Prob. 50ECh. 6.2 - Prob. 51ECh. 6.2 - Logic Puzzles Raymond Smullyan is one of todays...Ch. 6.2 - Prob. 53ECh. 6.3 - Prob. 1YTCh. 6.3 - Prob. 2YTCh. 6.3 - Prob. 3YTCh. 6.3 - Prob. 4YTCh. 6.3 - Prob. 5YTCh. 6.3 - Prob. 1WECh. 6.3 - Prob. 2WECh. 6.3 - Prob. 1ECh. 6.3 - Prob. 2ECh. 6.3 - Prob. 3ECh. 6.3 - Prob. 4ECh. 6.3 - Prob. 5ECh. 6.3 - Prob. 6ECh. 6.3 - Prob. 7ECh. 6.3 - Explain why the statement If 3 = 5, then 4 = 6 is...Ch. 6.3 - Prob. 9ECh. 6.3 - Tell whether each conditional is true or false....Ch. 6.3 - Prob. 11ECh. 6.3 - Prob. 12ECh. 6.3 - Prob. 13ECh. 6.3 - Prob. 14ECh. 6.3 - Prob. 15ECh. 6.3 - Prob. 16ECh. 6.3 - Prob. 17ECh. 6.3 - Let d represent My dog ate my homework, let f...Ch. 6.3 - Prob. 19ECh. 6.3 - Prob. 20ECh. 6.3 - Prob. 21ECh. 6.3 - Prob. 22ECh. 6.3 - Prob. 23ECh. 6.3 - Prob. 24ECh. 6.3 - Prob. 25ECh. 6.3 - Prob. 26ECh. 6.3 - Prob. 27ECh. 6.3 - Prob. 28ECh. 6.3 - Prob. 29ECh. 6.3 - Prob. 30ECh. 6.3 - Prob. 31ECh. 6.3 - What is the minimum number of times that F must...Ch. 6.3 - Prob. 33ECh. 6.3 - Construct a truth table for each statement....Ch. 6.3 - Construct a truth table for each statement....Ch. 6.3 - Construct a truth table for each statement....Ch. 6.3 - Prob. 37ECh. 6.3 - Prob. 38ECh. 6.3 - Prob. 39ECh. 6.3 - Prob. 40ECh. 6.3 - Prob. 41ECh. 6.3 - Prob. 42ECh. 6.3 - Prob. 43ECh. 6.3 - Prob. 44ECh. 6.3 - Prob. 45ECh. 6.3 - Prob. 46ECh. 6.3 - Prob. 47ECh. 6.3 - Prob. 48ECh. 6.3 - Prob. 49ECh. 6.3 - Prob. 50ECh. 6.3 - Prob. 51ECh. 6.3 - Prob. 52ECh. 6.3 - Prob. 53ECh. 6.3 - Prob. 54ECh. 6.3 - Prob. 55ECh. 6.3 - Prob. 56ECh. 6.3 - Prob. 57ECh. 6.3 - Prob. 58ECh. 6.3 - Prob. 59ECh. 6.3 - Prob. 60ECh. 6.3 - Prob. 61ECh. 6.3 - Prob. 62ECh. 6.3 - Prob. 63ECh. 6.3 - In Exercises 6168, construct a truth table to...Ch. 6.3 - Prob. 65ECh. 6.3 - Prob. 66ECh. 6.3 - Prob. 67ECh. 6.3 - Prob. 68ECh. 6.3 - Prob. 69ECh. 6.3 - Prob. 70ECh. 6.3 - Prob. 71ECh. 6.3 - Prob. 72ECh. 6.3 - Prob. 73ECh. 6.3 - Prob. 74ECh. 6.3 - Prob. 75ECh. 6.3 - Prob. 76ECh. 6.3 - Prob. 77ECh. 6.3 - Prob. 78ECh. 6.3 - Prob. 79ECh. 6.3 - Prob. 80ECh. 6.3 - Prob. 81ECh. 6.3 - Prob. 82ECh. 6.3 - Prob. 83ECh. 6.3 - Prob. 84ECh. 6.3 - Prob. 85ECh. 6.3 - Prob. 86ECh. 6.3 - Prob. 87ECh. 6.3 - Prob. 88ECh. 6.3 - Prob. 89ECh. 6.3 - Prob. 90ECh. 6.3 - Prob. 91ECh. 6.3 - Prob. 92ECh. 6.3 - Prob. 93ECh. 6.4 - Prob. 1YTCh. 6.4 - Prob. 2YTCh. 6.4 - Prob. 3YTCh. 6.4 - Prob. 1WECh. 6.4 - Construct a truth table for each statement. W2. q ...Ch. 6.4 - For each given statement, write (a) the converse,...Ch. 6.4 - Prob. 2ECh. 6.4 - Prob. 3ECh. 6.4 - Prob. 4ECh. 6.4 - Prob. 5ECh. 6.4 - For each given statement, write (a) the converse,...Ch. 6.4 - Prob. 7ECh. 6.4 - Prob. 8ECh. 6.4 - Prob. 9ECh. 6.4 - Prob. 10ECh. 6.4 - Prob. 11ECh. 6.4 - Prob. 12ECh. 6.4 - Write each statement in the form if p then q. 13....Ch. 6.4 - Write each statement in the form if p then q. 14....Ch. 6.4 - Write each statement in the form if p then q. 15....Ch. 6.4 - Prob. 16ECh. 6.4 - Prob. 17ECh. 6.4 - Prob. 18ECh. 6.4 - Prob. 19ECh. 6.4 - Write each statement in the form if p then q. 20....Ch. 6.4 - Prob. 21ECh. 6.4 - Prob. 22ECh. 6.4 - Prob. 23ECh. 6.4 - Prob. 24ECh. 6.4 - Prob. 25ECh. 6.4 - Prob. 26ECh. 6.4 - Prob. 27ECh. 6.4 - Prob. 28ECh. 6.4 - Prob. 29ECh. 6.4 - Prob. 30ECh. 6.4 - Prob. 31ECh. 6.4 - Prob. 32ECh. 6.4 - Prob. 33ECh. 6.4 - Prob. 34ECh. 6.4 - Prob. 35ECh. 6.4 - Prob. 36ECh. 6.4 - Prob. 37ECh. 6.4 - Prob. 38ECh. 6.4 - Prob. 39ECh. 6.4 - Construct a truth table for each statement. 40. (p...Ch. 6.4 - Income Tax The following excerpts appear in a...Ch. 6.4 - Prob. 42ECh. 6.4 - Prob. 43ECh. 6.4 - Prob. 44ECh. 6.4 - Prob. 45ECh. 6.4 - Prob. 46ECh. 6.4 - Prob. 47ECh. 6.4 - Prob. 48ECh. 6.4 - Political Development It has been argued that...Ch. 6.4 - Prob. 50ECh. 6.4 - Prob. 51ECh. 6.4 - Prob. 52ECh. 6.4 - Prob. 53ECh. 6.4 - Prob. 54ECh. 6.4 - Prob. 55ECh. 6.4 - Prob. 57ECh. 6.5 - Prob. 1YTCh. 6.5 - Prob. 2YTCh. 6.5 - Write the contrapositive of each statement, and...Ch. 6.5 - Write the contrapositive of each statement, and...Ch. 6.5 - Prob. 1ECh. 6.5 - Prob. 2ECh. 6.5 - Prob. 3ECh. 6.5 - Prob. 4ECh. 6.5 - Prob. 5ECh. 6.5 - Prob. 6ECh. 6.5 - Prob. 7ECh. 6.5 - Prob. 8ECh. 6.5 - Prob. 9ECh. 6.5 - Each of the following arguments is either valid by...Ch. 6.5 - Each of the following arguments is either valid by...Ch. 6.5 - Prob. 12ECh. 6.5 - Prob. 13ECh. 6.5 - Prob. 14ECh. 6.5 - Prob. 15ECh. 6.5 - Prob. 16ECh. 6.5 - Prob. 17ECh. 6.5 - Prob. 18ECh. 6.5 - Prob. 19ECh. 6.5 - Prob. 20ECh. 6.5 - Prob. 21ECh. 6.5 - Prob. 22ECh. 6.5 - Prob. 23ECh. 6.5 - Prob. 24ECh. 6.5 - Prob. 25ECh. 6.5 - Prob. 26ECh. 6.5 - Prob. 27ECh. 6.5 - Prob. 28ECh. 6.5 - Prob. 29ECh. 6.5 - Prob. 30ECh. 6.5 - Prob. 31ECh. 6.5 - For Exercises 2937, determine whether each of the...Ch. 6.5 - Prob. 33ECh. 6.5 - Prob. 34ECh. 6.5 - For Exercises 2937, determine whether each of the...Ch. 6.5 - Prob. 36ECh. 6.5 - Prob. 37ECh. 6.5 - Prob. 38ECh. 6.5 - Prob. 39ECh. 6.5 - Prob. 40ECh. 6.5 - Prob. 41ECh. 6.5 - Prob. 42ECh. 6.5 - Prob. 43ECh. 6.5 - Prob. 44ECh. 6.6 - Prob. 1YTCh. 6.6 - Prob. 2YTCh. 6.6 - Prob. 3YTCh. 6.6 - Prob. 4YTCh. 6.6 - Prob. 5YTCh. 6.6 - Give an assignment of truth values to the...Ch. 6.6 - Prob. 2WECh. 6.6 - For Exercises 16, (a) write the statement...Ch. 6.6 - Prob. 2ECh. 6.6 - Prob. 3ECh. 6.6 - Prob. 4ECh. 6.6 - Prob. 5ECh. 6.6 - Prob. 6ECh. 6.6 - Prob. 7ECh. 6.6 - Prob. 8ECh. 6.6 - Prob. 9ECh. 6.6 - Prob. 10ECh. 6.6 - Prob. 11ECh. 6.6 - Prob. 12ECh. 6.6 - Prob. 13ECh. 6.6 - Prob. 14ECh. 6.6 - Prob. 15ECh. 6.6 - Prob. 16ECh. 6.6 - Prob. 17ECh. 6.6 - Prob. 18ECh. 6.6 - In Exercises 720, (a) represent the argument...Ch. 6.6 - Prob. 20ECh. 6.6 - Prob. 21ECh. 6.6 - Prob. 22ECh. 6.6 - Prob. 23ECh. 6.6 - Prob. 24ECh. 6.6 - Prob. 25ECh. 6.6 - Prob. 26ECh. 6.6 - Prob. 27ECh. 6.6 - Prob. 28ECh. 6.6 - Prob. 29ECh. 6.6 - Prob. 30ECh. 6.6 - Prob. 31ECh. 6.6 - Prob. 32ECh. 6.6 - Prob. 33ECh. 6.6 - Prob. 34ECh. 6.6 - Prob. 35ECh. 6.6 - Prob. 36ECh. 6.6 - Prob. 37ECh. 6.6 - Prob. 38ECh. 6.6 - Prob. 39ECh. 6.6 - Constitution Each of the following exercises gives...Ch. 6.6 - Constitution Each of the following exercises gives...Ch. 6.6 - Prob. 42ECh. 6.6 - Prob. 43ECh. 6.6 - Prob. 44ECh. 6.6 - Prob. 45ECh. 6.6 - Prob. 46ECh. 6.6 - Prob. 47ECh. 6.6 - Prob. 48ECh. 6 - Determine whether each of the following statements...Ch. 6 - Prob. 2RECh. 6 - Prob. 3RECh. 6 - Determine whether each of the following statements...Ch. 6 - Prob. 5RECh. 6 - Prob. 6RECh. 6 - Prob. 7RECh. 6 - Prob. 8RECh. 6 - Prob. 9RECh. 6 - Prob. 10RECh. 6 - Prob. 11RECh. 6 - Prob. 12RECh. 6 - Prob. 13RECh. 6 - Prob. 14RECh. 6 - Prob. 15RECh. 6 - Prob. 16RECh. 6 - Prob. 17RECh. 6 - Prob. 18RECh. 6 - Prob. 19RECh. 6 - Prob. 20RECh. 6 - Prob. 21RECh. 6 - Prob. 22RECh. 6 - Prob. 23RECh. 6 - Prob. 24RECh. 6 - Prob. 25RECh. 6 - Prob. 26RECh. 6 - Prob. 27RECh. 6 - Prob. 28RECh. 6 - Prob. 29RECh. 6 - Prob. 30RECh. 6 - Prob. 31RECh. 6 - Prob. 32RECh. 6 - Prob. 33RECh. 6 - Prob. 34RECh. 6 - Prob. 35RECh. 6 - Prob. 36RECh. 6 - Prob. 37RECh. 6 - Prob. 38RECh. 6 - Prob. 39RECh. 6 - Prob. 40RECh. 6 - Prob. 41RECh. 6 - Prob. 43RECh. 6 - Prob. 44RECh. 6 - Prob. 45RECh. 6 - Prob. 46RECh. 6 - Prob. 47RECh. 6 - Prob. 48RECh. 6 - Prob. 49RECh. 6 - Prob. 50RECh. 6 - Prob. 51RECh. 6 - Prob. 52RECh. 6 - Prob. 53RECh. 6 - Prob. 54RECh. 6 - Prob. 55RECh. 6 - In Exercises 55 and 56, (a) represent the argument...Ch. 6 - Prob. 57RECh. 6 - Prob. 58RECh. 6 - Prob. 59RECh. 6 - Prob. 60RECh. 6 - Prob. 61RECh. 6 - Prob. 64RECh. 6 - Prob. 65RECh. 6 - Prob. 66RECh. 6 - Prob. 67RECh. 6 - Prob. 68RECh. 6 - Prob. 69RECh. 6 - Prob. 70RECh. 6 - Prob. 71RECh. 6 - Prob. 72RECh. 6 - Prob. 73RECh. 6 - Prob. 74RECh. 6 - Prob. 75RECh. 6 - Lewis Carroll The following exercises are from...Ch. 6 - Prob. 77RECh. 6 - Lewis Carroll The following exercises are from...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, calculus and related others by exploring similar questions and additional content below.Similar questions
- Cancel Done RESET Suppose that R(x) is a polynomial of degree 7 whose coefficients are real numbers. Also, suppose that R(x) has the following zeros. -1-4i, -3i, 5+i Answer the following. (a) Find another zero of R(x). ☐ | | | | |│ | | | -1 བ ¢ Live Adjust Filters Croparrow_forwardSuppose that R (x) is a polynomial of degree 7 whose coefficients are real numbers. Also, suppose that R (x) has the following zeros. -1-4i, -3i, 5+i Answer the following. (c) What is the maximum number of nonreal zeros that R (x) can have? ☐arrow_forwardSuppose that R (x) is a polynomial of degree 7 whose coefficients are real numbers. Also, suppose that R (x) has the following zeros. -1-4i, -3i, 5+i Answer the following. (b) What is the maximum number of real zeros that R (x) can have? ☐arrow_forward
- i need help please dont use chat gptarrow_forward3.1 Limits 1. If lim f(x)=-6 and lim f(x)=5, then lim f(x). Explain your choice. x+3° x+3* x+3 (a) Is 5 (c) Does not exist (b) is 6 (d) is infinitearrow_forward1 pts Let F and G be vector fields such that ▼ × F(0, 0, 0) = (0.76, -9.78, 3.29), G(0, 0, 0) = (−3.99, 6.15, 2.94), and G is irrotational. Then sin(5V (F × G)) at (0, 0, 0) is Question 1 -0.246 0.072 -0.934 0.478 -0.914 -0.855 0.710 0.262 .arrow_forward
- 2. Answer the following questions. (A) [50%] Given the vector field F(x, y, z) = (x²y, e", yz²), verify the differential identity Vx (VF) V(V •F) - V²F (B) [50%] Remark. You are confined to use the differential identities. Let u and v be scalar fields, and F be a vector field given by F = (Vu) x (Vv) (i) Show that F is solenoidal (or incompressible). (ii) Show that G = (uvv – vVu) is a vector potential for F.arrow_forwardA driver is traveling along a straight road when a buffalo runs into the street. This driver has a reaction time of 0.75 seconds. When the driver sees the buffalo he is traveling at 44 ft/s, his car can decelerate at 2 ft/s^2 when the brakes are applied. What is the stopping distance between when the driver first saw the buffalo, to when the car stops.arrow_forwardTopic 2 Evaluate S x dx, using u-substitution. Then find the integral using 1-x2 trigonometric substitution. Discuss the results! Topic 3 Explain what an elementary anti-derivative is. Then consider the following ex integrals: fed dx x 1 Sdx In x Joseph Liouville proved that the first integral does not have an elementary anti- derivative Use this fact to prove that the second integral does not have an elementary anti-derivative. (hint: use an appropriate u-substitution!)arrow_forward
- 1. Given the vector field F(x, y, z) = -xi, verify the relation 1 V.F(0,0,0) = lim 0+ volume inside Se ff F• Nds SE where SE is the surface enclosing a cube centred at the origin and having edges of length 2€. Then, determine if the origin is sink or source.arrow_forward4 3 2 -5 4-3 -2 -1 1 2 3 4 5 12 23 -4 The function graphed above is: Increasing on the interval(s) Decreasing on the interval(s)arrow_forwardQuestion 4 The plot below represents the function f(x) 8 7 3 pts O -4-3-2-1 6 5 4 3 2 + 1 2 3 5 -2+ Evaluate f(3) f(3) = Solve f(x) = 3 x= Question 5arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Elementary Geometry For College Students, 7eGeometryISBN:9781337614085Author:Alexander, Daniel C.; Koeberlein, Geralyn M.Publisher:Cengage,
Elementary Geometry For College Students, 7e
Geometry
ISBN:9781337614085
Author:Alexander, Daniel C.; Koeberlein, Geralyn M.
Publisher:Cengage,
Grade 12 and UG/ Introduction to logical statements and truth tables; Author: Dr Trefor Bazett;https://www.youtube.com/watch?v=q2eyZZK-OIk;License: Standard YouTube License, CC-BY