The only given information is the time in 3 seconds. We are asked to find the position, or the distance traveled. The working equation to be used here is:
x = v₀t + 1/2 at²
where
x is the distance
v₀ is the initial velocity
a is the acceleration
In order to solve this, let's assume the object is free falling. So v₀ = 0 and a = 9.81 m/s².
x = 0 + 1/2 (9.81)(3)²
x = 44.145 meters