The Acceleration of Gravity on Earth Is Approximately 10 M/s2

Multiple Choice

The acceleration of gravity on Earth is approximately 10 m/s2 (more precisely, 9.8 m/s2) . If you drop a rock from a tall building, about how fast will it be falling after 3 seconds?

A) 20 m/s
B) 10 m/s
C) 10 m/s2
D) 30 m/s
E) 30 m/s2