A ball is launched horizontally at a speed of $10.0\,\text{m s}^{-1}$ over level ground. It reaches the ground after $3.0\,\text{s}$. Air resistance is negligible. What is the speed of the ball immediately before impact?
- A$10\,\text{m s}^{-1}$
- B$29\,\text{m s}^{-1}$
- C$31\,\text{m s}^{-1}$
- D$39\,\text{m s}^{-1}$