Answer:
25 m/s in the opposite direction with the ship recoil velocity.
Explanation:
Assume the ship recoil velocity and velocity of the cannon ball aligns. By the law of momentum conservation, the momentum is conserved before and after the shooting. Before the shooting, the total momentum is 0 due to system is at rest. Therefore, the total momentum after the shooting must also be 0:
where 
are masses of the ship and ball respectively. 
are the velocities of the ship and ball respectively, after the shooting.
So the cannon ball has a velocity of 25 m/s in the opposite direction with the ship recoil velocity.
I believe C is your answer (also, I am also using tht same exact program!)
pigsExplanation: population
Potential energy can be calculated using the following rule:
potential energy = mgh where:
m is the mass = 85 kg
g is the acceleration due to gravity = 9.8 m/sec^2
h is the height = 4 km = 4000 meters
Substitute in the above equation to get the potential energy as follows:
Potential energy = 85*9.8*4000 = 3332000 joules
The lens equation gives d relation between focal length, object distance n image distance.
1/f = 1/v + 1/u
seldon
