A 25.0 kg child plays on a swing with support ropes that are 2.10 m long. A friend pulls her back until the ropes are 43.0° from the vertical and releases her from rest. What is the child's speed at the bottom of the swing?

a. It depends on the release angle.
b. 9.8 m/s
c. 4.9 m/s
d. 14.7 m/s