A horizontal spring is lying on a frictionless surface. One end of the spring is attaches to a wall while the other end is connected to a movable object. The spring and object are compressed by 0.070 m, released from rest, and subsequently oscillate back and forth with an angular frequency of 17.2 rad/s. What is the speed of the object at the instant when the spring is stretched by 0.042 m relative to its unstrained length?