2. (Hour30) Find the length of the part of the astroid :5 = (3033 t, y = sin3 15 in the rst quadrant (that is, from t = 0 to t = 7r/2). Hint: the trig identity, sin2 t + 0052 t = 1 might be useful. 3. (Hour29) Find parametric equations and a parameter interval for the motion of a particle that moves along the graph of y = 3:2 in the following way: Beginning at (0,0) it moves to (2,4), and then travels back and forth from (2,4) to (2,4) innitely many times. Hint: periodic functions might be useful