11. Assume the total number of dollars (in billions) on entertainment in the United States from 1990 to 2000 can be approximated by the model S = 148 + 6.7t + 0.58t2. where t =
0 represents the year 1990. During which year was $215 billion the amount spent on entertainment? (5 points)
12. Solve 3x2 - 10x = 8 by factoring. (5 points)
13. Express 3x2 + 3y2 + 18x - 30y = 6 in the standard form for a circle. Identify the radius and center of the circle. (5 points)
15. The price of a certain stock was $54 a share in April of this year. In November the price of the same stock was $38 a share.
a. Assuming the stock price declined at a constant rate, write a linear equation to give the price P in terms of the month m. (Hint: Let the month of January be 1. Set the rest of the month values based on that starting point.) (3 points)
b. Based on your equation in part a, what was the price of the stock in August? (2 points)