
College Algebra
1st Edition
ISBN: 9781938168383
Author: Jay Abramson
Publisher: OpenStax
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 4, Problem 4RE
Determine whether the
Expert Solution & Answer

Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Given the cubic function f(x) = x^3-6x^2 + 11x- 6, do the following: Plot the graph of the
function. Find the critical points and determine whether each is a local minimum, local
maximum, or a saddle point. Find the inflection point(s) (if any).Identify the intervals where
the function is increasing and decreasing. Determine the end behavior of the graph.
Given the quadratic function f(x) = x^2-4x+3, plot the graph of the function and find the
following: The vertex of the parabola .The x-intercepts (if any). The y-intercept. Create graph
also before solve.
what model best fits this data
Chapter 4 Solutions
College Algebra
Ch. 4.1 - If f(x) is a linear function, and (2,3) and (0,4)...Ch. 4.1 - The population of a small town increased from...Ch. 4.1 - If f(x) is a linear function, with f(2)=11, and...Ch. 4.1 - A new plant food was introduced to a young tree to...Ch. 4.1 - Graph f(x)=34x+6 by plotting points.Ch. 4.1 - Find a point on the graph we drew in Example 12...Ch. 4.1 - Graph f(x)=4+2x, using transformations.Ch. 4.1 - Find the x-intercept of f(x)=14x4.Ch. 4.1 - Given the function h(x)=2x4, write an equation for...Ch. 4.1 - A line passes through the points, (2,15) and...
Ch. 4.1 - Terry is skiing down a steep hill. Terry’s...Ch. 4.1 - Jessica is walking home from a friend’s...Ch. 4.1 - A boat is 100 miles away from the marina,...Ch. 4.1 - If the graphs of two linear functions...Ch. 4.1 - Ifa horizontal line has the equation f(x)=a and...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, determine whether...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, given each set of...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, determine whether the...Ch. 4.1 - For the following exercises, find the x-and...Ch. 4.1 - For the following exercises, find the x- and...Ch. 4.1 - For the following exercises, find the x-and...Ch. 4.1 - For the following exercises, find the x-and...Ch. 4.1 - For the following exercises, find the x-and...Ch. 4.1 - For the following exercises, find the x-and...Ch. 4.1 - For the following exercises, use the descriptions...Ch. 4.1 - For the following exercises, use the descriptions...Ch. 4.1 - For the following exercises, use the descriptions...Ch. 4.1 - For the following exercises, use the descriptions...Ch. 4.1 - For the following exercises, use the descriptions...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, find the slope of the...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, write an equation for...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, match the given...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch a line with...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, sketch the graph of...Ch. 4.1 - For the following exercises, write the equation of...Ch. 4.1 - For the following exercises, write the equation of...Ch. 4.1 - For the following exercises, write the equation of...Ch. 4.1 - For the following exercises, write the equation of...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, which of the tables...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - For the following exercises, use a calculator or...Ch. 4.1 - Find the value ofx if a linear function goes...Ch. 4.1 - Find the value ofy if a linear function goes...Ch. 4.1 - Find the equation of the line that passes...Ch. 4.1 - Find the equation of the line that passes...Ch. 4.1 - Find the equation of the line that passes...Ch. 4.1 - Find the equation of the line parallel to the line...Ch. 4.1 - Find the equation of the line perpendicular to the...Ch. 4.1 - For the following exercises, use the functions...Ch. 4.1 - For the following exercises, use the functions...Ch. 4.1 - At noon, a barista notices that she has 20 in...Ch. 4.1 - A gym membership with two personal...Ch. 4.1 - A clothing business finds there is a...Ch. 4.1 - A phone company charges for service accordingto...Ch. 4.1 - A farmer finds there is a linear relationship...Ch. 4.1 - A city’s population in the year 1960 was...Ch. 4.1 - A town’s population has been growing linearly.In...Ch. 4.1 - Suppose that average annual income (in dollars)...Ch. 4.1 - When temperature is 0 degrees Celsius,...Ch. 4.2 - A company sells doughnuts. They incur a fixed cost...Ch. 4.2 - A city’s population has been growing linearly. In...Ch. 4.2 - Try it #3 There is a straight road leading from...Ch. 4.2 - Explain how to find the input variable in a word...Ch. 4.2 - Explain how to find the output variable in a wordp...Ch. 4.2 - Explain how to interpret the initial value in a...Ch. 4.2 - Explain how to determine the slope in a...Ch. 4.2 - Find the area of a parallelogram bounded by...Ch. 4.2 - Find the area of a triangle bounded by the...Ch. 4.2 - Find the area of a triangle bounded by the...Ch. 4.2 - Find the area of a parallelogram bounded by...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, consider this...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the graph in...Ch. 4.2 - For the following exercises, use the median home...Ch. 4.2 - For the following exercises, use the median home...Ch. 4.2 - NUMERIC For the following exercises, use the...Ch. 4.2 - For the following exercises, use the median home...Ch. 4.2 - For the following exercises, use the median home...Ch. 4.2 - For the following exercises, use the median home...Ch. 4.2 - In 2004, a school population was 1,001. By 2008the...Ch. 4.2 - In 2003, a town’s population was 1,431. By 2007the...Ch. 4.2 - A phone company has a monthly cellular plan where...Ch. 4.2 - A phone company has a monthly cellular data plan...Ch. 4.2 - In 1991, the moose population in a park...Ch. 4.2 - In 2003, the owl population in a park was measured...Ch. 4.2 - The Federal Helium Reserve held about 16...Ch. 4.2 - Suppose the world’s oil reserves in 2014 are 1,820...Ch. 4.2 - You are choosing between two different prepaid...Ch. 4.2 - You are choosing between two different...Ch. 4.2 - When hired at a new job selling jewelry, you...Ch. 4.2 - When hired at a new job selling electronics, you...Ch. 4.2 - When hired at a new job selling electronics, you...Ch. 4.2 - When hired at a new job selling electronics, you...Ch. 4.3 - According to the data from Table 1, what...Ch. 4.3 - Use the model we created using technology in...Ch. 4.3 - Describe what it means if there is a model...Ch. 4.3 - What is interpolation when using a linear model?Ch. 4.3 - What is extrapolation when using a linear model?Ch. 4.3 - Explain the difference between a positive and...Ch. 4.3 - Explain how to interpret the absolute value of...Ch. 4.3 - A regression was run to determine whether there...Ch. 4.3 - A regression was run to determine whether there is...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, draw a scatter plot...Ch. 4.3 - For the following exercises, match each...Ch. 4.3 - For the following exercises, match each...Ch. 4.3 - For the following exercises, match each...Ch. 4.3 - For the following exercises, match each...Ch. 4.3 - For the following exercises, draw a best-fit line...Ch. 4.3 - For the following exercises, draw a best-fit line...Ch. 4.3 - For the following exercises, draw a best-fit line...Ch. 4.3 - For the following exercises, draw a best-fit line...Ch. 4.3 - The U.S. Census tracks the percentage of persons...Ch. 4.3 - The US. import of wine (in hectoliters) for...Ch. 4.3 - Table 6 shows the year and the number ofpeople...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - For the following exercises, use each set of data...Ch. 4.3 - Graph f(x)=0.5x+10. Pick a set of 5 orderedpairs...Ch. 4.3 - Graph f(x)=2x10. Picka set of5 ordered pairs using...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4.3 - For the following exercises, consider this...Ch. 4 - Determine whether the algebraic equation is...Ch. 4 - Determine whether the algebraic equation is...Ch. 4 - Determine whether the function is increasing...Ch. 4 - Determine whether the function is increasing...Ch. 4 - Given each set of information, find a linear...Ch. 4 - Given each set of information, find a linear...Ch. 4 - Find the slope of the line shown in the graph.Ch. 4 - Find the slope of the line shown in the graph.Ch. 4 - Write an equation in slope-intercept form for the...Ch. 4 - Does the following table represent a linear...Ch. 4 - Does the following table represent a linear...Ch. 4 - On June 1st, a company has $4,000,000 profit.If...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, find the x-and...Ch. 4 - For the following exercises, find the x-and...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - For the following exercises, use the descriptions...Ch. 4 - Find the area of a triangle bounded by the y-axis,...Ch. 4 - A town’s population increases at a constant rate....Ch. 4 - The number of people afflicted with the common...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercise, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - Draw a scatter plot for the data in Table 2. Then...Ch. 4 - Draw a scatter plot for the data in Table 3. If we...Ch. 4 - Eight students were asked to estimate their score...Ch. 4 - Draw a best-fit line for the plotted data.Ch. 4 - For the following exercises, consider the data in...Ch. 4 - For the following exercises, consider the data in...Ch. 4 - For the following exercises, consider the data in...Ch. 4 - For the following exercises, consider the data in...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - Determine whether the following algebraic...Ch. 4 - Determine whether the following function...Ch. 4 - Determine whether the following function...Ch. 4 - Given the following set of information, find a...Ch. 4 - Given the following set of information. find a...Ch. 4 - Find the slope ofthe line in Figure l.Ch. 4 - Write an equation for line in Figure 2.Ch. 4 - Does Table 1 represent a linear function? If so,...Ch. 4 - Does Table 2 represent a linear function? If so,...Ch. 4 - At 6 am, an online company has sold 120 items that...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, determine whether the...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use the graph in...Ch. 4 - For the following exercises, use Table 4 which...Ch. 4 - For the following exercises, use Table 4 which...Ch. 4 - For the following exercises, use Table 4 which...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...Ch. 4 - For the following exercises, consider this...
Additional Math Textbook Solutions
Find more solutions based on key concepts
Fill in each blank so that the resulting statement is true. An equation that expresses a relationship between t...
Algebra and Trigonometry (6th Edition)
A child has 12 blocks, of which 6 are black, 4 are red, 1 is white, and 1 is blue. If the child puts the blocks...
A First Course in Probability (10th Edition)
4. Correlation and Causation What is meant by the statement that “correlation does imply causation”?
Elementary Statistics
If you multiply an odd number by 2 and add 1, is your answer even or odd?
A Problem Solving Approach To Mathematics For Elementary School Teachers (13th Edition)
In Exercises 5–20, conduct the hypothesis test and provide the test statistic and the P-value and for critical ...
Elementary Statistics (13th Edition)
x−n and xn with the help of example.
Pre-Algebra Student Edition
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, algebra and related others by exploring similar questions and additional content below.Similar questions
- Round as specified A) 257 down to the nearest 10’s place B) 650 to the nearest even hundreds, place C) 593 to the nearest 10’s place D) 4157 to the nearest hundreds, place E) 7126 to the nearest thousand place arrow_forwardEstimate the following products in two different ways and explain each method  A) 52x39 B) 17x74 C) 88x11 D) 26x42arrow_forwardFind a range estimate for these problems A) 57x1924 B) 1349x45 C) 547x73951arrow_forward
- Draw the image of the following figure after a dilation centered at the origin with a scale factor of 14 退 14 12- 10 5- + Z 6 的 A X 10 12 14 16 18 G min 3 5arrow_forwardkofi makes a candle as a gift for his mom. The candle is a cube with a volume of 8/125 ft cubed. Kofi wants to paint each face of the candle exepct for the bottom. what is the area he will paint?arrow_forward10 6 9. 8 -7- 6. 5. 4- 3. 2 1- -1 0 -1 2 3 4 ·10 5 6 7 00 8 6 10arrow_forward
- Week 3: Mortgages and Amortiza X + rses/167748/assignments/5379530?module_item_id=23896312 11:59pm Points 10 Submitting an external tool Gider the following monthly amortization schedule: Payment # Payment Interest Debt Payment Balance 1 1,167.34 540.54 626.80 259,873.20 2 1,167.34 539.24 628.10 259,245.10 3 1,167.34 With the exception of column one, all amounts are in dollars. Calculate the annual interest rate on this loa Round your answer to the nearest hundredth of a percent. Do NOT round until you calculate the final answer. * Previous a Earrow_forwardCafé Michigan's manager, Gary Stark, suspects that demand for mocha latte coffees depends on the price being charged. Based on historical observations, Gary has gathered the following data, which show the numbers of these coffees sold over six different price values: Price Number Sold $2.70 765 $3.50 515 $2.00 990 $4.30 240 $3.10 325 $4.00 475 Using simple linear regression and given that the price per cup is $1.85, the forecasted demand for mocha latte coffees will be cups (enter your response rounded to one decimal place).arrow_forwardGiven the correlation coefficient (r-value), determine the strength of the relationship. Defend your answersarrow_forward
- ??!!arrow_forwardrections: For problem rough 3, read each question carefully and be sure to show all work. 1. Determine if 9(4a²-4ab+b²) = (6a-3b)² is a polynomial identity. 2. Is (2x-y) (8x3+ y³) equivalent to 16x4-y4? 3. Find an expression that is equivalent to (a - b)³. Directions: For problems 4 and 5, algebraically prove that the following equations are polynomial identities. Show all of your work and explain each step. 4. (2x+5)² = 4x(x+5)+25 5. (4x+6y)(x-2y)=2(2x²-xy-6y²)arrow_forwardName: Mussels & bem A section of a river currently has a population of 20 zebra mussels. The population of zebra mussels increases 60 % each month. What will be the population of zebra mussels after 2 years? 9 10 # of months # of mussels 1 2 3 4 5 6 7 8 o Graph your data. Remember to title your graph. What scale should be used on the y-axis? What scale should be used on the x-axis? Exponential Growth Equation y = a(1+r)*arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Big Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin HarcourtAlgebra: Structure And Method, Book 1AlgebraISBN:9780395977224Author:Richard G. Brown, Mary P. Dolciani, Robert H. Sorgenfrey, William L. ColePublisher:McDougal LittellHolt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL
- Trigonometry (MindTap Course List)TrigonometryISBN:9781337278461Author:Ron LarsonPublisher:Cengage LearningAlgebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:CengageGlencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill

Big Ideas Math A Bridge To Success Algebra 1: Stu...
Algebra
ISBN:9781680331141
Author:HOUGHTON MIFFLIN HARCOURT
Publisher:Houghton Mifflin Harcourt

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

Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL

Trigonometry (MindTap Course List)
Trigonometry
ISBN:9781337278461
Author:Ron Larson
Publisher:Cengage Learning
Algebra & Trigonometry with Analytic Geometry
Algebra
ISBN:9781133382119
Author:Swokowski
Publisher:Cengage

Glencoe Algebra 1, Student Edition, 9780079039897...
Algebra
ISBN:9780079039897
Author:Carter
Publisher:McGraw Hill
Finding Local Maxima and Minima by Differentiation; Author: Professor Dave Explains;https://www.youtube.com/watch?v=pvLj1s7SOtk;License: Standard YouTube License, CC-BY