Answer:
0.86 m
Step-by-step explanation:
We can solve the problem by using the law of conservation of energy.
The initial mechanical energy of the flower pot is just gravitational potential energy, given by:

where
m = 2.50 kg is the mass of the pot
g = 9.8 m/s^2 is the acceleration due to gravity
h = 12.0 m is the height
When the pot hits and compresses the spring coming to a stop, all this energy is converted into elastic potential energy of the spring:

where
k = 800 N/m is the spring constant
x is the compression of the spring
Due to the conservation of energy,

So we can write
