Need exerc 3,4,5

a) Use a graphing calculator or spreadsheet to make a scatter plot of this data. (b) Find an equation of the least squares regression line and graph it with your data. (c) Use the regression line model to predict the public debt in 2018. (3) A company charges the following shipping fees for its internet orders. For orders up to $24.99, they charge $2.99 in shipping. For orders between $25.00 and $49.99, they charge $4.99 shipping. For orders of $50.00 or more, shipping is free. Graph the shipping fee as a function of the order price. (4) A town produces a portion of its electricity using windmills. Suppose that with winds that average s miles/hour, the windmills generate p(s) = v1500s kilowatts of power. The town estimates that f(x) = 0.28x is the number of people that can be supported by x kilowatts. (a) Write a formula for the function r(s) = f(p(s)). What does r measure? (b) Computer(18) and interpret your result in this context. (5) The value of a car is given by V(t) = 22500(0.74) , where t is the number of years after the car is purchased. When will the car be worth $3000? (Be sure to show your work, or describe how you used your device to get your answer. Don't just answer with a number.) (6) Market researchers estimate that the percentage of households that have viewed a particular television program is given by the following function: 0.13 f ( + )