Explanation:
For the equilibrium:
\rho_{wood}gh-\rho_{oil}g(h-x)-\rho_{water}gx=0ρ
wood
gh−ρ
oil
g(h−x)−ρ
water
gx=0
\rho_{wood}h-\rho_{oil}(h-x)-\rho_{water}x=0ρ
wood
h−ρ
oil
(h−x)−ρ
water
x=0
(974)(3.97)-928(3.97-x)-1000x=0(974)(3.97)−928(3.97−x)−1000x=0
x=2.54\ cmx=2.54 cm
The formula of the kinetic energy is:

where m is a mass of the object, v is speed of the object at the moment of time. So we have:

The answer is
2000 Joules.