4. The table shows the average cost, in dollars, of a movie ticket in the United States for different years Year 1948 1963 1974 1978 1985 1991 1997 2005 2010 Cost 0.36 0.86 1.89 2.34 3.55 4.21 4.59 6.41 7.89 Use technology to answer the following: (a) Find the equation of the least squares regression line. Round values of a and b to four decimal places. (b) Find r. Round to three decimal places. Interpret the r-value. (c) Find 74. Round to three decimal places. Tell what it means. (d) Use the equation of the least squares regression line to predict the average cost of a movie ticket in 1995