Question 152220
d=distance
t=time
K=constant of proportion
the distance of a falling object is directly proportionae to the square of the time it falls before hitting ground 
then d=Kt^2
the object fell 144 ft in 3 seconds 
then 144=K(3)^2
then 144=9K
then K=16
then equation is d=16t^2

so if t =4 d=16(4)^2=16^2=256
Answer: it falls 256 ft after 4 seconds