(a) on a separate sheet of paper, sketch the parameterized curve x=tcost, y=tsint for 0? t? 4? . use your graph to complete the following statement: at t=4, a particle moving along the curve in the direction of increasing t is moving down and to the right (b) by calculating the position at t=4 and t=4.01, estimate the speed at t=4. speed ? (c) use derivatives to calculate the speed at t=4 and compare your answer to part (b). speed =