To test a depth of the well a person drops a rock down from the well the rock takes 2.9 seconds to hit the water bill out how deep is the well

Question

Help me please 

Answer 1

This involves free fall due to gravity.  The equation is:  d = 0.5 gt² where g is the acceleration due to gravity, 9.8 m/s², t is time in seconds.  From there, solve the math.