82. National Debt The size of the total debt owed by the United States federal government continues to grow. In fact, according to the Department of the Treasury, the debt per person living in the United States is approximately (or over per U.S. household). The following data represent the U.S. debt for the years 2001—2014. Since the debt D depends on the year y, and each input corresponds to exactly one output, the debt is a function of the year. So D(y) represents the debt for each year y.
(a) Plot the points , , and so on in a Cartesian plane.
(b) Draw a line segment from the point to . What does the slope of this line segment represent?
(c) Find the average rate of change of the debt from 2002 to 2004.
(d) Find the average rate of change of the debt from 2006 to 2008.
(e) Find the average rate of change of the debt from 2010 to 2012.
(f) What appears to be happening to the average rate of change as time passes?
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Precalculus Enhanced with Graphing Utilities (7th Edition)
- World Military Expenditure The following chart shows total military and arms trade expenditure from 2011–2020 (t = 1 represents 2011). †A bar graph titled "World military expenditure" has a horizontal t-axis labeled "Year since 2010" and a vertical axis labeled "$ (billions)". The bar graph has 10 bars. Each bar is associated with a label and an approximate value as listed below. 1: 1,800 billion dollars 2: 1,775 billion dollars 3: 1,750 billion dollars 4: 1,730 billion dollars 5: 1,760 billion dollars 6: 1,760 billion dollars 7: 1,850 billion dollars 8: 1,900 billion dollars 9: 1,950 billion dollars 10: 1,980 billion dollars (a) If you want to model the expenditure figures with a function of the form f(t) = at2 + bt + c, would you expect the coefficient a to be positive or negative? Why? HINT [See "Features of a Parabola" in this section.] We would expect the coefficient to be positive because the curve is concave up. We would expect the coefficient to be negative because the…arrow_forwardEXERCISE 1.3arrow_forwardThe table shows the historical in-state tuition rates for the University of Kalamazoo. Use the data to answer the questions and round your answers to two decimal places. Academic year Rate of tuition for one semester 2008–2009 $3,812 2009–2010 $4,002 2010–2011 $4,441 2011–2012 $4,905 2012–2013 $5,181 What is the percentage increase in tuition from the 2008–2009 school year to the 2012–2013 school year?arrow_forward
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- Algebra & Trigonometry with Analytic GeometryAlgebraISBN:9781133382119Author:SwokowskiPublisher:Cengage