PART B A graphing calculator is required on this part of the exam. 8. At time t, the position of a particle in the xy-plane is given by the parametric function f (t) = (x(t), y(t)), where x (t) = Vt (t-1) and y(t) = (cost) (In(t+1)) for t=0 to t=5 seconds. At which of the following times does the path of the particle intersect the line y = 2x? (A) 1.399 seconds (B) 1.449 seconds (C) 1.491 seconds (D) 1.571 seconds AP Precalculus Course FrameworkResidual Plot 9. The relationship between two variables in a certain scenario is modeled with a linear function. The residual plot for the linear regression is given. Which of the following reasoned conclusions is the best interpretation of the residual plot? (A) A linear function is valid because the residual plot demonstrates a pattern. B) A linear function is invalid because the residual plot demonstrates a pattern. C) A linear function is valid because the residual plot demonstrates no pattern. (D) A linear function is invalid because the residual plot demonstrates no pattern. 10. In a certain region around a major city, the number of megawatts drawn from the power grid at different times was calculated. The function M given by M (t) =-0.3t* +15.3t -268t2 + 1954t -2668 models the number of megawatts drawn t hours after midnight. The model is only consistent with the data for 4