Question 2 2 pts Four waves are described by the following equations, where distances are measured in meters and times in seconds. 1. y = 0.12 cos(3x - 21t) 1I. y = 0.15 cos(6x + 42t) y = 0.13 cos(6x + 21t) IV. y = -0.23 cos(3x - 42t) Which of these waves have the same period? I and Ill, and also II and IV I and IV, and also II and Ill O I and Il, and also Ill and IV O All of them have the same period. O They all have different periods. Question 3 2 pts A steel wire of mass 0.400 kg and length 0.640 m supports a 102-kg block. The wire is struck exactly at its midpoint causing a small displacement. How long does it take the peak of this displacement to reach the top of the wire? O 1.6:10 3 s O 2.00x10-3 s O 4.00x10-3 s 6.00x10 3 s O 8.00x10 3 s