How fast is the ball moving just as it lands?

How fast is the ball moving just as it lands? One way to measure g on another planet or moon by remote sensing is to measure how long it takes an object to fall a given distance. A lander vehicle on a distant planet records the fact that it takes 4.50 s for a ball to fall freely 12.52 m, starting from rest.

A. What is the acceleration due to gravity on that planet? Express your answer in m/s^2.

B. What is the acceleration due to gravity on that planet? Express your answer in earth g’s.

C. How fast is the ball moving just as it lands?