FUNCTIONS AND CHANGE COMBO
6th Edition
ISBN: 9781337801287
Author: Crauder
Publisher: MCGRAW-HILL HIGHER EDUCATION
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 1.2, Problem 1E
Minimum Wage The table below is taken from the website of the U.S. Department of Labor. It shows the minimum wage for each decade from 1950 to 2010. The figures are adjusted for inflation and expressed in constant 2012 dollars.
|
|
|
| 1950 |
|
| 1960 |
|
| 1970 |
|
| 1980 |
|
| 1990 |
|
| 2000 |
|
| 2010 |
|
a. Find the value of
b. Use functional notation to express the minimum wage in 1985.
c. Use the table to estimate the minimum wage in 1985. (The actual value was
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Solve for the matrix X:
X
(2 7³) x + ( 2 ) - (112)
6
14
8
5.
Solve for the matrix X. (Hint: we can solve AX
-1
= B whenever A is invertible)
2
3
0
Χ
2
=
3
1
Write p(x) = 6+11x+6x² as a linear combination of ƒ (x) = 2+x+4x² and g(x) = 1−x+3x²
and h(x)=3+2x+5x²
Chapter 1 Solutions
FUNCTIONS AND CHANGE COMBO
Ch. 1.1 - Explain the meaning of G(4,3,2) and calculate its...Ch. 1.1 - What is your monthly payment if you borrow 5000 at...Ch. 1.1 - Movie Tickets According to information provided by...Ch. 1.1 - McDonalds The formula M(t)=1.19t+13.22 gives the...Ch. 1.1 - Speed from Skid Marks When a car makes an...Ch. 1.1 - Harris-Benedict Formula Your basal metabolic rate...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Gross Profit Margin The gross profit margin is a...Ch. 1.1 - Tax Owed The income tax T owed in a certain state...Ch. 1.1 - Reminder Round all answers to two decimal places...
Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Round all answers to two decimal places unless...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Prob. 16ECh. 1.1 - Round all answers to two decimal places unless...Ch. 1.1 - Prob. 18ECh. 1.1 - Prob. 19ECh. 1.1 - Prob. 20ECh. 1.1 - Prob. 21ECh. 1.1 - ReminderRound all answers to two decimal places...Ch. 1.1 - ReminderRound all answers to two decimal places...Ch. 1.1 - ReminderRound all answers to two decimal places...Ch. 1.1 - Prob. 25ECh. 1.1 - ReminderRound all answers to two decimal places...Ch. 1.1 - Prob. 27ECh. 1.1 - Prob. 28ECh. 1.1 - Prob. 29ECh. 1.1 - Prob. 30ECh. 1.1 - Reminder Round all answers to two decimal places...Ch. 1.1 - Prob. 32ECh. 1.1 - Prob. 1SBECh. 1.1 - Prob. 2SBECh. 1.1 - Prob. 3SBECh. 1.1 - Prob. 4SBECh. 1.1 - Prob. 5SBECh. 1.1 - Prob. 6SBECh. 1.1 - Evaluating Formulas In Exercises S-1 through S-24,...Ch. 1.1 - Prob. 8SBECh. 1.1 - Prob. 9SBECh. 1.1 - Prob. 10SBECh. 1.1 - Prob. 11SBECh. 1.1 - Prob. 12SBECh. 1.1 - Prob. 13SBECh. 1.1 - Prob. 14SBECh. 1.1 - Prob. 15SBECh. 1.1 - Evaluating Formulas In Exercises S-1 through S-24,...Ch. 1.1 - Prob. 17SBECh. 1.1 - Prob. 18SBECh. 1.1 - Prob. 19SBECh. 1.1 - Prob. 20SBECh. 1.1 - Prob. 21SBECh. 1.1 - Prob. 22SBECh. 1.1 - Prob. 23SBECh. 1.1 - Prob. 24SBECh. 1.1 - Prob. 25SBECh. 1.1 - What Formulas Mean In Exercises S-25 through S-33,...Ch. 1.1 - Prob. 27SBECh. 1.1 - What Formulas Mean In Exercises S-25 through S-33,...Ch. 1.1 - Prob. 29SBECh. 1.1 - Prob. 30SBECh. 1.1 - Prob. 31SBECh. 1.1 - Prob. 32SBECh. 1.1 - What Formulas Mean In Exercises S-25 through S-33,...Ch. 1.2 - TEST YOUR UNDERSTANDING|FOR EXAMPLE 1.3 Use the...Ch. 1.2 - Use the table of values you made in part 4 of the...Ch. 1.2 - Minimum Wage The table below is taken from the...Ch. 1.2 - Mortgage Rates The following table is taken from...Ch. 1.2 - Box Office Hits The table below shows the highest...Ch. 1.2 - Mobile Phone Sales In 2000, mobile handset sales...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Freight on Class I Railroads According to the...Ch. 1.2 - The American Food Dollar The following table shows...Ch. 1.2 - Gross Domestic Product The following table shows...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - A Troublesome Snowball One winter afternoon,...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Prob. 15ECh. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Prob. 23ECh. 1.2 - Round all answers to two decimal places unless...Ch. 1.2 - Round all answers to two decimal places unless...Ch. 1.2 - Prob. 26ECh. 1.2 - Prob. 27ECh. 1.2 - Reminder Round all answers to two decimal places...Ch. 1.2 - Prob. 1SBECh. 1.2 - Prob. 2SBECh. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - Prob. 4SBECh. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - Prob. 6SBECh. 1.2 - Prob. 7SBECh. 1.2 - Prob. 8SBECh. 1.2 - Prob. 9SBECh. 1.2 - Prob. 10SBECh. 1.2 - Prob. 11SBECh. 1.2 - Prob. 12SBECh. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - Prob. 14SBECh. 1.2 - Prob. 15SBECh. 1.2 - Prob. 16SBECh. 1.2 - Prob. 17SBECh. 1.2 - Prob. 18SBECh. 1.2 - Prob. 19SBECh. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - Prob. 21SBECh. 1.2 - Prob. 22SBECh. 1.2 - Prob. 23SBECh. 1.2 - Prob. 24SBECh. 1.2 - Prob. 25SBECh. 1.2 - Prob. 26SBECh. 1.2 - Prob. 27SBECh. 1.2 - Prob. 28SBECh. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - For these exercises, round all estimates to one...Ch. 1.2 - When Limiting Values Occur Suppose S(t) represents...Ch. 1.2 - Does a Limiting Value Occur? A rocket ship is...Ch. 1.3 - TEST YOUR UNDERSTANDING | FOR EXAMPLE 1.5 From...Ch. 1.3 - TEST YOUR UNDERSTANDING | FOR EXAMPLE 1.6 Locate a...Ch. 1.3 - Prob. 3TUCh. 1.3 - Prob. 4TUCh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Reminder Round all answers to two decimal places...Ch. 1.3 - Prob. 5ECh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Prob. 8ECh. 1.3 - Prob. 9ECh. 1.3 - Prob. 10ECh. 1.3 - Prob. 11ECh. 1.3 - Prob. 12ECh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Prob. 14ECh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Prob. 19ECh. 1.3 - Prob. 20ECh. 1.3 - Prob. 21ECh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Prob. 23ECh. 1.3 - ReminderRound all answers to two decimal places...Ch. 1.3 - Prob. 25ECh. 1.3 - Prob. 26ECh. 1.3 - Prob. 27ECh. 1.3 - Reminder Round all answers to two decimal places...Ch. 1.3 - Prob. 29ECh. 1.3 - Prob. 30ECh. 1.3 - Prob. 31ECh. 1.3 - Prob. 1SBECh. 1.3 - Prob. 2SBECh. 1.3 - Prob. 3SBECh. 1.3 - Prob. 4SBECh. 1.3 - Prob. 5SBECh. 1.3 - Prob. 6SBECh. 1.3 - Prob. 7SBECh. 1.3 - Prob. 8SBECh. 1.3 - Prob. 9SBECh. 1.3 - Prob. 10SBECh. 1.3 - Prob. 11SBECh. 1.3 - Prob. 12SBECh. 1.3 - Prob. 13SBECh. 1.3 - Prob. 14SBECh. 1.3 - Prob. 15SBECh. 1.3 - Prob. 16SBECh. 1.3 - Prob. 17SBECh. 1.3 - A Function Given by a Graph The following is the...Ch. 1.3 - Prob. 19SBECh. 1.3 - Prob. 20SBECh. 1.3 - Prob. 21SBECh. 1.3 - Prob. 22SBECh. 1.3 - Prob. 23SBECh. 1.3 - Prob. 24SBECh. 1.3 - Prob. 25SBECh. 1.3 - Prob. 26SBECh. 1.3 - Prob. 27SBECh. 1.3 - Prob. 28SBECh. 1.3 - Prob. 29SBECh. 1.3 - Prob. 30SBECh. 1.3 - Prob. 31SBECh. 1.3 - Prob. 32SBECh. 1.3 - Prob. 33SBECh. 1.3 - Prob. 34SBECh. 1.3 - Prob. 35SBECh. 1.4 - TEST YOUR UNDERSTANDING Suppose we start with 9...Ch. 1.4 - Prob. 2TUCh. 1.4 - Prob. 3TUCh. 1.4 - Prob. 4TUCh. 1.4 - Prob. 1ECh. 1.4 - Prob. 2ECh. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - 5. United States Population Growth In 1960 the...Ch. 1.4 - Prob. 6ECh. 1.4 - a. Use a formula to express the altitude of a...Ch. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - Remainder: Round all answer to two decimal places...Ch. 1.4 - m Miles per Gallon The cost of operating a car...Ch. 1.4 - Prob. 13ECh. 1.4 - Continued This is a continuation of Exercise 13....Ch. 1.4 - Reminder: Round all answer to two decimal places...Ch. 1.4 - Reminder Round all answers to two decimal places...Ch. 1.4 - Reminder Round all answers to two decimal places...Ch. 1.4 - Reminder Round all answers to two decimal places...Ch. 1.4 - Reminder Round all answers to two decimal places...Ch. 1.4 - Reminder:-Round all answers to two decimal places...Ch. 1.4 - Reminder Round all answers to two decimal places...Ch. 1.4 - Prob. 22ECh. 1.4 - Prob. 23ECh. 1.4 - ReminderRound all answers to two decimal places...Ch. 1.4 - Reminder:-Round all answers to two decimal places...Ch. 1.4 - Prob. 26ECh. 1.4 - Prob. 27ECh. 1.4 - Hubbles Constant Astronomers believe that the...Ch. 1.4 - Prob. 29ECh. 1.4 - Prob. 30ECh. 1.4 - Prob. 1SBECh. 1.4 - Light It is 93,000,000 miles from the earth to the...Ch. 1.4 - Prob. 3SBECh. 1.4 - Getting a Formula In Exercises S-4 through S-13, a...Ch. 1.4 - Prob. 5SBECh. 1.4 - Getting a Formula In Exercises S-4 through S-13, a...Ch. 1.4 - Getting a Formula In Exercises S-4 through S-13, a...Ch. 1.4 - Prob. 8SBECh. 1.4 - Prob. 9SBECh. 1.4 - Prob. 10SBECh. 1.4 - Prob. 11SBECh. 1.4 - Getting a Formula In Exercises S-4 through S-13, a...Ch. 1.4 - Getting a Formula In Exercises S-4 through S-13, a...Ch. 1.4 - Prob. 14SBECh. 1.4 - Prob. 15SBECh. 1.4 - Prob. 16SBECh. 1.4 - Is it Proportional? In Exercises S-17 through...Ch. 1.4 - Prob. 18SBECh. 1.4 - Prob. 19SBECh. 1.4 - Prob. 20SBECh. 1.4 - Prob. 21SBECh. 1.4 - Is it Proportional? In Exercises S17 through S25,...Ch. 1.4 - Prob. 23SBECh. 1.4 - Prob. 24SBECh. 1.4 - Is it Proportional? In Exercises S17 through S25,...Ch. 1.CR - Prob. 1CRCh. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Prob. 5CRCh. 1.CR - Prob. 6CRCh. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Round all answers to two decimal places unless...Ch. 1.CR - Prob. 11CRCh. 1.CR - Prob. 12CRCh. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Prob. 14CRCh. 1.CR - Prob. 15CRCh. 1.CR - Prob. 16CRCh. 1.CR - Reminder Round all answers to two decimal places...Ch. 1.CR - Prob. 18CRCh. 1.FR1 - Prob. 1TUCh. 1.FR1 - Prob. 1ECh. 1.FR1 - Prob. 2ECh. 1.FR1 - Prob. 3ECh. 1.FR1 - Prob. 4ECh. 1.FR1 - Prob. 5ECh. 1.FR1 - Prob. 6ECh. 1.FR1 - Prob. 7ECh. 1.FR1 - Prob. 8ECh. 1.FR1 - Prob. 9ECh. 1.FR1 - Prob. 10ECh. 1.FR1 - Prob. 11ECh. 1.FR1 - Prob. 12ECh. 1.FR1 - Prob. 13ECh. 1.FR2 - Prob. 1TUCh. 1.FR2 - Prob. 2TUCh. 1.FR2 - Prob. 1ECh. 1.FR2 - Prob. 2ECh. 1.FR2 - Prob. 3ECh. 1.FR2 - Prob. 4ECh. 1.FR2 - Prob. 5ECh. 1.FR2 - Prob. 6ECh. 1.FR2 - Prob. 7ECh. 1.FR2 - Prob. 8ECh. 1.FR2 - Prob. 9ECh. 1.FR2 - Prob. 10ECh. 1.FR2 - Prob. 11ECh. 1.FR2 - Prob. 12ECh. 1.FR3 - If f(x)=x+3x1, find f(2).Ch. 1.FR3 - Prob. 2ECh. 1.FR3 - Prob. 3ECh. 1.FR3 - If f(x)=xx2, find f(x2). Hint: Replace x in the...Ch. 1.FR3 - Prob. 5ECh. 1.FR3 - Prob. 6ECh. 1.FR3 - Prob. 7ECh. 1.FR3 - Prob. 8ECh. 1.FR3 - Prob. 9ECh. 1.FR3 - Prob. 10E
Additional Math Textbook Solutions
Find more solutions based on key concepts
(a) Make a stem-and-leaf plot for these 24 observations on the number of customers who used a down-town CitiBan...
APPLIED STAT.IN BUS.+ECONOMICS
Evaluate the integrals in Exercises 1–46.
1.
University Calculus: Early Transcendentals (4th Edition)
1. How is a sample related to a population?
Elementary Statistics: Picturing the World (7th Edition)
CHECK POINT I Consider the six jokes about books by Groucho Marx. Bob Blitzer. Steven Wright, HennyYoungman. Je...
Thinking Mathematically (6th Edition)
The largest polynomial that divides evenly into a list of polynomials is called the _______.
Elementary & Intermediate Algebra
23. A plant nursery sells two sizes of oak trees to landscapers. Large trees cost the nursery $120 from the gro...
College Algebra (Collegiate Math)
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
- 3. Let M = (a) - (b) 2 −1 1 -1 2 7 4 -22 Find a basis for Col(M). Find a basis for Null(M).arrow_forwardSchoology X 1. IXL-Write a system of X Project Check #5 | Schx Thomas Edison essay, x Untitled presentation ixl.com/math/algebra-1/write-a-system-of-equations-given-a-graph d.net bookmarks Play Gimkit! - Enter... Imported Imported (1) Thomas Edison Inv... ◄›) What system of equations does the graph show? -8 -6 -4 -2 y 8 LO 6 4 2 -2 -4 -6 -8. 2 4 6 8 Write the equations in slope-intercept form. Simplify any fractions. y = y = = 00 S olo 20arrow_forwardEXERCICE 2: 6.5 points Le plan complexe est rapporté à un repère orthonormé (O, u, v ).Soit [0,[. 1/a. Résoudre dans l'équation (E₁): z2-2z+2 = 0. Ecrire les solutions sous forme exponentielle. I b. En déduire les solutions de l'équation (E2): z6-2 z³ + 2 = 0. 1-2 2/ Résoudre dans C l'équation (E): z² - 2z+1+e2i0 = 0. Ecrire les solutions sous forme exponentielle. 3/ On considère les points A, B et C d'affixes respectives: ZA = 1 + ie 10, zB = 1-ie 10 et zc = 2. a. Déterminer l'ensemble EA décrit par le point A lorsque e varie sur [0, 1. b. Calculer l'affixe du milieu K du segment [AB]. C. Déduire l'ensemble EB décrit par le point B lorsque varie sur [0,¹ [. d. Montrer que OACB est un parallelogramme. e. Donner une mesure de l'angle orienté (OA, OB) puis déterminer pour que OACB soit un carré.arrow_forward
- 2 Use grouping to factor: 10x + 13x + 3 = 0 Identify A B and C in the chart below feach responce inarrow_forward2 Use grouping to factor: 10x² + 13x + 3 = 0 Identify A, B, and C in the chart below. (each rearrow_forward2 Use grouping to factor: 10x + 13x + 3 = 0 Identify A B and C in the chart below feach responce inarrow_forward
- Use grouping to fully factor: x³ + 3x² - 16x - 48 = 0 3 2arrow_forwardName: Tay Jones Level Two Date: Algebra 3 Unit 3: Functions and Equations Practice Assessment Class: #7-OneNote 1. The function f(x) = x² is transformed in the following functions. List the vertex for each function, circle whether the function opens up or down, and why. All three parts must be correct to receive Level 2 points. You can receive points for a, b, and c. a) g(x) = -2(x+5)² Vertex: Opens Up Opens Down Why? ais negative -2 Vertex: b) g(x) = (x + 2)² - 3 c) g(x) = -4(x + 2)² + 2 Opens Up Opens Down Vertex: Opens Up Opens Down Why? 4 Ca is negative) Why? his positive 2. The graph of the function f(x) is shown below. Find the domain, range, and end behavior. Then list the values of x for which the function values are increasing and decreasing. f(x) Domain: End Behavior: As x → ∞o, f(x) -> -6 As x, f(x) -> Range: Where is it Increasing? (002] Where is it Decreasing? (1,00)arrow_forwardShow what to do on the graph visually please!arrow_forward
- The county's new asphalt paving machine can surface 1 km of highway in 10 h. A much older machine can surface 1 km in 18 h. How long will it take them to surface 21 km of highway if they start at opposite ends and work day and night?arrow_forward3. Write a system of linear equations in slope intercept form that has exactly one solution at the point (3, 4), such that one line has positive slope (but not 1) and the other line has negative slope (but not "1). Also write your system of equations with both equations written in standard form with out any fractions 8- 7 8 5 4 3 -2- + -8-7-6-5-4-3-2-1 1 2 3 -1 2 - ° 4 -5 - -8arrow_forward2. Write a system of linear equations in slope-intercept form has exactly one solution at the point (3, 4), such that both lines have negative slope (but neither one has slope of 1). Also write your system of equations with both equations written in standard form without any fractions. B 0 5 4 3 -2 1 -8-7-6-5-4-3-2 -1 12 3 -1 2 -3 -5 6 -7 -8arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
College AlgebraAlgebraISBN:9781305115545Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
Algebra and Trigonometry (MindTap Course List)AlgebraISBN:9781305071742Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
College Algebra (MindTap Course List)AlgebraISBN:9781305652231Author:R. David Gustafson, Jeff HughesPublisher:Cengage Learning
Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage Learning
Mathematics For Machine TechnologyAdvanced MathISBN:9781337798310Author:Peterson, John.Publisher:Cengage Learning,
Holt Mcdougal Larson Pre-algebra: Student Edition...AlgebraISBN:9780547587776Author:HOLT MCDOUGALPublisher:HOLT MCDOUGAL
College Algebra
Algebra
ISBN:9781305115545
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
Algebra and Trigonometry (MindTap Course List)
Algebra
ISBN:9781305071742
Author:James Stewart, Lothar Redlin, Saleem Watson
Publisher:Cengage Learning
College Algebra (MindTap Course List)
Algebra
ISBN:9781305652231
Author:R. David Gustafson, Jeff Hughes
Publisher:Cengage Learning
Functions and Change: A Modeling Approach to Coll...
Algebra
ISBN:9781337111348
Author:Bruce Crauder, Benny Evans, Alan Noell
Publisher:Cengage Learning
Mathematics For Machine Technology
Advanced Math
ISBN:9781337798310
Author:Peterson, John.
Publisher:Cengage Learning,
Holt Mcdougal Larson Pre-algebra: Student Edition...
Algebra
ISBN:9780547587776
Author:HOLT MCDOUGAL
Publisher:HOLT MCDOUGAL
Implicit Differentiation with Transcendental Functions; Author: Mathispower4u;https://www.youtube.com/watch?v=16WoO59R88w;License: Standard YouTube License, CC-BY
How to determine the difference between an algebraic and transcendental expression; Author: Study Force;https://www.youtube.com/watch?v=xRht10w7ZOE;License: Standard YouTube License, CC-BY